Identical Polarization Research Articles

Ferroelectrics everywhere: Ferroelectricity in magnesium substituted zinc oxide thin films

We demonstrate ferroelectricity in Mg-substituted ZnO thin films with the wurtzite structure. Zn1−xMgxO films are grown by dual-cathode reactive magnetron sputtering on (111)-Pt // (0001)-Al2O3 substrates at temperatures ranging from 26 to 200 °C for compositions spanning from x = 0 to x = 0.37. X-ray diffraction indicates a decrease in the c-lattice parameter and an increase in the a-lattice parameter with increasing Mg content, resulting in a nearly constant c/a axial ratio of 1.595 over this composition range. Transmission electron microscopy studies show abrupt interfaces between Zn1−xMgxO films and the Pt electrode. When prepared at pO2 = 0.025, film surfaces are populated by abnormally oriented grains as measured by atomic force microscopy for Mg concentrations >29%. Raising pO2 to 0.25 eliminates the misoriented grains. Optical measurements show increasing bandgap values with increasing Mg content. When prepared on a 200 °C substrate, films display ferroelectric switching with remanent polarizations exceeding 100 μC cm−2 and coercive fields below 3 MV cm−1 when the Mg content is between ∼30% and ∼37%. Substrate temperature can be lowered to ambient conditions, and when doing so, capacitor stacks show only minor sacrifices to crystal orientation and nearly identical remanent polarization values; however, coercive fields drop below 2 MV/cm. Using ambient temperature deposition, we demonstrate ferroelectric capacitor stacks integrated directly with polymer substrate surfaces.

Insights into surface alkaline-earth segregation on the surface of La0.3Me0.7Fe0.7Cr0.3O3−δ (Me = Sr, Ca) porous electrodes for oxygen reduction reaction

Surface alkaline-earth segregation is a common problem encountered for the cathodes of solid oxide fuels cells based on perovskites (ABO3) containing alkaline-earth acceptor dopants. In this work, the porous electrodes of La0.3Me0.7Fe0.7Cr0.3O3−δ (Me = Sr, Ca) were employed as the model specimens to look into the surface segregation issue. The two electrodes were cathodically polarized by continuously testing their cathodic current polarization curves. The electrocatalytic activity of the two electrodes was examined in relation with their cathodic polarization history. Moreover, the crystal and surface structures of the cathodically polarized electrodes were analyzed. An appreciable segregation of strontium onto the surface was detected for cathodically polarized La0.3Sr0.7Fe0.7Cr0.3O3−δ electrode, leading to an obvious deceleration of disassociative adsorption of molecular oxygen on the surface and thus degradation of the electrode activity. In contrast, La0.3Ca0.7Fe0.7Cr0.3O3−δ electrode displayed nearly negligible surface calcium segregation and degradation of the electrocatalytic activity after experiencing an identical cathodic polarization history. The disparity of the two electrodes was related to their A-site compositions. This work exemplifies the importance of minimizing A-site cation size mismatch in stabilizing the crystal structure of the perovskite electrodes under cathodic polarization conditions and therefore alleviating the segregation of A-site alkaline-earth cations onto the electrode surface.

Design of a Stacked Co-Polarized Full-Duplex Antenna With Broadside Radiation

This article presents a co-linearly polarized (LP) stacked two-port antenna with compact size and broadside radiation patterns for in-band full-duplex (IBFD) application. The proposed IBFD antenna consists of a patch antenna and a substrate integrated waveguide (SIW) cavity-backed slot antenna (CBSA). The patch antenna and the CBSA are used as the transmitter (Tx) and receiver (Rx), respectively. The Rx is placed above the Tx for compact size. Linear polarization and broadside radiation patterns are achieved in this article. A cavity-patch coupling (CPC) path is added for canceling the slot-patch coupling (SPC) by using four probes to connect the top layer of the SIW cavity and the metal ground. Parametric studies show that the two coupling paths can be adjusted independently. Experimental results illustrate that the measured highest isolation over 40 dB is obtained with a compact size of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$30\times 30\times {4}$ </tex-math></inline-formula> mm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup> ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.63\lambda _{0} \times 0.63\lambda _{0} \times 0.08\lambda _{0}$ </tex-math></inline-formula> , <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\lambda _{0}$ </tex-math></inline-formula> is the free-space wavelength at the center frequency of about 6.29 GHz). The measured −10 dB bandwidths of the Tx and Rx antennas are 430 and 100 MHz, respectively. The proposed stacked IBFD antenna is validated with the merits of identical polarization, same radiation direction, and compact size.

Trust in information, political identity and the brain: an interdisciplinary fMRI study.

Misinformation has triggered government inquiries and threatens the perceived legitimacy of campaign processes and electoral outcomes. A new identity polarization has arisen between Remain and Leave sympathizers in the UK Brexit debate, with associated accusations of misinformation use. Competing psychological accounts of how people come to accept and defend misinformation pit self-reinforcing motivated cognition against lack of systematic reasoning as possible explanations. We harness insights from political science, cognitive neuroscience and psychology to examine the impact of trust and identity on information processing regarding Brexit in a group of Remain identifiers. Behaviourally, participants' affective responses to Brexit-related information are affected by whether the emotional valence of the message is compatible with their beliefs on Brexit (positive/negative) but not by their trust in the source of information. However, belief in the information is significantly affected by both (dis)trust in information source and by belief compatibility with the valence of the information. Neuroimaging results confirm this pattern, identifying areas involved in judgements of the self, others and automatic processing of affectively threatening stimuli, ultimately supporting motivated cognition accounts of misinformation endorsement.This article is part of the theme issue ‘The political brain: neurocognitive and computational mechanisms’.

Facebook Profiles of Major Tv News Stations in Poland on June 4, 2019

The increase in the polarization level and identity divisions of the Polish society have become possible due to the existence of new media, including social media, especially Facebook. It is in the space of mass media where individual identity narratives, concerning the experience of individual memory of individual actors and the interpretation of history, take place. Among the important events in the recent history of Poland, which have become a part of the identity division and polarization processes, were the partially free elections on June 4, 1989. The quality and quantity of the material presented on the 30th anniversary of these elections on the official Facebook accounts of the main Polish TV news stations confirms that the media remain not neutral to key events and phenomena in the social space. Moreover, they contribute to deepening and consolidating certain moods and the phenomenon of polarization. The mediatization process affects not only the adaptation of individual units or institutions to the mentality of the media, but also the phenomenon of media adaptation to the expectations of its users.

Hybrid Subarray Using a New Concept of Feed for Advanced Antenna and Array Designs

This work explores a hybrid subarray where a pair of dielectric resonator antennas (DRAs) are fed with identical phase and polarization by a resonant microstrip patch sharing a common grounded substrate. The elegance of the structure is to maintain the resonance features of the individual patch and DRA elements resulting in a large radiating aperture and improved gain. A C-band design promises 9.5-12.5 dBi gain indicating 5 dB improvement on average compared to that of the individual elements. Accurate deployment required for effective feeding of the DRAs in the subarray and the subarray sidelobe-level dependence on its aperture fields has been discussed. A comprehensive design guideline has been presented to enable one to accurately designing it in any specified frequency within the given limit. This antenna has been experimented to realize different array configurations. The linear array featuring zero interelement spacing emerges as a compact high-gain configuration with a reduced number of feed requirements. Typically, a 1.75 subarray unit (5 elements linear) to 2 subarray unit (rectangular) array is found to result inasmuch as 14.5 dBi peak gain. This design should find potential applications where high gain is required using minimal feeding structures.

A comparative study of surface segregation and interface of La0·6Sr0·4Co0·2Fe0·8O3-δ electrode on GDC and YSZ electrolytes of solid oxide fuel cells

Electrode/electrolyte interface plays a critical role in the performance and stability of solid oxide fuel cells (SOFCs). In the case of La0·6Sr0·4Co0·2Fe0·8O3-δ (LSCF) cathode, it is well known that cathodic polarization promotes the Sr segregation and diffusion towards the LSCF electrode and Y2O3–ZrO2 (YSZ) electrolyte interface, leading to the formation of SrZrO3 secondary phase and the disintegration of LSCF structure at the interface. On the other hand, LSCF is chemically stable with doped ceria electrolytes such as Gd-doped CeO2 (GDC). However, there appears no comparative studies on the intrinsic relationship between the surface segregation, interface reaction and stability of LSCF in YSZ and GDC electrolytes. Here, a comparative study has been carried out on the segregation and interface formation of LSCF on GDC and YSZ electrolyte under identical cathodic polarization conditions at 750 °C and 1000 mAcm−2 using focused ion beam and scanning transmission electron microscopy (FIB-STEM) techniques. Segregation of Sr occurs in the LSCF-GDC system, however, the inertness of GDC electrolyte suppresses the segregation process of Sr species. Instead, surface segregation of B-site Co cation becomes dominant under the cathodic polarization, forming isolated CoOx particles. The results indicate that the existence of chemical catchers such as Zr in the case of YSZ electrolyte for the segregated Sr species is kinetically the driving force for the Sr segregation and stability of LSCF electrodes under SOFC operation conditions.

Influence of the Corrosiveness of a Medium on the Ratio of the Cathodic Protection Current to the Ultimate Diffusion Current for KH70 Pipe Steel

We study the dependence of the ratio of the cathodic protection current to the ultimate diffusion current for Kh70 steel within the range of protective polarization potentials (-0.75)–(-1.05) V (relative to the silver-chloride reference electrode) standardized by the DSTU 4219 in media with different degrees of corrosiveness. It is shown that, within the рН range 5.6–9.6, as the potential shifts to more negative values, the ratio $$ {j}_{\mathrm{c}.\mathrm{p}.}/{j}_{{\mathrm{O}}_2} $$ increases from 0.5 to 138. It was discovered that, for the identical protective polarization potentials in a section of the gas main, the corrosion rate in a defect of the protective coating of steel may not only decrease but also activate the process of hydrogen reduction. It is reasonable to determine a value of the ratio $$ {j}_{\mathrm{c}.\mathrm{p}.}/{j}_{{\mathrm{O}}_2} $$ above which the process of decomposition of soil electrolytes is accelerated and the hydrogenation of the pipe wall in a defect of the coating becomes possible for every medium and take into account this value both in the design of the cathodic protection and in the process of monitoring in the course of operation to prevent stress-corrosion cracking.

Entrepreneuring after 50: the liminal identity transitions of older emergent entrepreneurs

ABSTRACT Entrepreneurship has been proposed as a solution to extending working lives. However, little is known about how older (50+) entrepreneurs manage their personal transitions into entrepreneurship. In this paper, we propose to use a liminal identity work perspective to explore the identity paradoxes that older entrepreneurs experience during their transition into entrepreneurship and how they manage it. We use a qualitative study conducted over 14 months in the United Kingdom. Our analysis shows how older entrepreneurs confront identity paradoxes, interruptions and identity polarization in their attempts to shift from older identities and activity patterns into new ones. The entrepreneurs who manage to overcome the identity interruptions and polarization that the transition brings move away from an initial sense of isolation and bring creative understandings to older entrepreneuring processes. Our results expand current understanding of entrepreneurial identity work in liminal conditions, especially among older entrepreneurs, by looking at the tensions emerging between potentially new and customary identities and behaviours as an important aspect of entrepreneuring transitions rather than as negative frictions to be avoided.

Training a Multi-Layer Photonic Spiking Neural Network With Modified Supervised Learning Algorithm Based on Photonic STDP

We propose a framework for hardware architecture and learning algorithm co-design of multi-layer photonic spiking neural network (SNN). The vertical-cavity surface-emitting laser with an embedded saturable absorber (VCSEL-SA) which contains two polarization-resolved modes is employed as a spiking neuron. The connection between two identical polarization modes is considered as the excitatory synapse, whereas the connection between two orthogonal polarization modes is regarded as the inhibitory synapse. The physical model of the photonic spiking neuron is derived based on the combination of spin-flip model and Yamada model. The photonic spike timing dependent plasticity (STDP) is applied to design a hardware-friendly biologically plausible supervised learning algorithm for a multi-layer photonic SNN. Thanks to the polarization mode competition effect in the VCSEL-SA, the proposed neuromorphic network is capable of solving the classical XOR problem. The effect of physical parameters of photonic neuron on the training convergence is also considered. We further extend the multi-layer photonic SNN to realize other logic learning tasks. To the best of our knowledge, such a modified supervised learning algorithm dedicated for a multi-layer photonic SNN has not yet been reported, which is interesting for spiking learning of neuromorphic photonics.

Nation branding, cultural identity and political polarization – an exploratory framework

PurposeThe objective of this research is to propose a framework which is apt to assess how a nation branding campaign could promote cultural identity by ultimately curbing political polarization.Design/methodology/approachBy relying on a multidisciplinary approach that blends theoretical constructs from different fields the methodology is based on a mixed-method approach whereby the qualitative data stemming from a set of interviews with key-informants is coupled by a survey of Colombian citizens in order to gain in-depth insights over the impact of nation branding on political polarization.FindingsFrom the findings, it emerges that a campaign based on nation branding and targeting domestic citizens could curb political polarization within Colombia, by also fostering cultural identity.Research limitations/implicationsThe study considers only Colombia. To fully assess the robustness of the framework it would be useful to extend the analysis to a broader range of countries and to a wider set of domestic issues.Practical implicationsThe research not only provides in-depth insights on how nation branding can be used effectively in order to curb political polarization but also practical guidance on how a nation branding campaign can be effectively designed. The findings are relevant to policy-makers that have the opportunity to implement informed and educated nation branding campaigns not just overseas, but also to strategically address important domestic issues by engaging the domestic stakeholders.Originality/valueWhile country branding has been extensively investigated within the context of international business, we have a relatively limited understanding of its domestic impact. In contrast to traditional country branding literature, this paper aims to theoretically advance our understanding of nation branding and its effect on political polarization, as well as gauging its impact on cultural identity.

High-power spectral beamsplitter for closely spaced frequencies.

An experimental realization of a compact, high-power spectral beamsplitter for nearly equal frequencies and identical polarization based on two-beam interference in a free-space Mach-Zehnder interferometer is presented. We demonstrate the power- and cost-efficient generation and subsequent spatial separation of two laser tones from a single sum-frequency-generation stage using double-sideband suppressed-carrier modulation in the infrared, and beam splitting in the visible at high power. The interferometer spectrally splits >98 % of the incident power when accounting for bulk absorption. The beamsplitter can be constructed identically for any power or spectral range required for which suitable optics are available.

Broadband printed MIMO dipole antenna for 2.4 GHz WLAN applications

Broadband printed dipole antenna with elliptical-arms and integrated balun for multiple-input-multiple-output (MIMO) antennas at 2.4 GHz frequency is designed and presented. The MIMO structure is composed of four symmetrical dipole elements and a circular ground plane. To enhance the isolation between contiguous elements, they are placed in a perpendicular direction. Isolation of parallel dipoles with identical polarization is guaranteed by a suitable distance. Outstanding impedance matching, good isolation, high-gain, and stable directional radiation pattern are advantages of this design. Structural simplicity is achieved by printing dipole arms, balun structure, and the ground plane on FR4 substrates. The proposed MIMO antenna is manufactured and tested in the anechoic chamber. The empirical results have a proper discrepancy with the simulation outcomes.

A coding metasurface antenna array with low radar cross section

An aperiodic metasurface antenna array with low radar cross section (RCS) is designed. The upper patches of the two antenna elements have the same shape and are placed at an orthogonal position, which can effectively reduce the workload of simulating the reflection characteristics of the patch. As antenna elements, they have identical operational band and polarization mode, and as metasurfaces, they can form an effective phase difference of 180° ± 37°. The RCS of the array is reduced mainly by phase cancellation under the &lt;i&gt;x&lt;/i&gt; polarization and by absorption under the &lt;i&gt;y&lt;/i&gt; polarization. According to the coding metamaterial theory, the two elements can be coded aperiodically by using the programming software. Regarding element A and element B as “0” and “1”, respectively, the coding matrix can be solved by a genetic algorithm. Element A and element B are arranged according to positions “0” and “1” to obtain a proposed array. The scattering field of proposed array is diffusive, and the peak RCS is effectively reduced. In order to highlight the characteristics of the proposed array, the chessboard-type array is designed for comparison. The simulation results show that the radiation performance of proposed array is good. Comparing with the metal board of the same size, the 6 dB reduction bandwidth of the monostatic RCS is 4.8－7.4 GHz (relative bandwidth is 42.6%) under the &lt;i&gt;x&lt;/i&gt; polarization and 4.6－7.8 GHz (relative bandwidth is 51.6%) under the &lt;i&gt;y&lt;/i&gt; polarization. Comparing with the chessboard type array, the scattering energy distribution of the designed antenna array is very uniform and the peak RCS in space reduces obviously. When a 4.8 GHz electromagnetic wave is incident with different incident angles and polarization modes, the scattering field is diffusive. Compared with other similar arrays, the proposed array has advantages of simple design process and even scattering field. The experimental results are in good agreement with the simulation results. This work makes full use of the scattering characteristics of the antenna element itself to solve the problem that the array antenna possesses both good radiation characteristics and low scattering characteristics at the same time, and improves the design process of the antenna patch. This design method has certain universality and reference significance for designing the low RCS antenna array.

Brexit as the outcome of the ambivalent British policy towards European integration

Based on the analysis of the political processes and challenges during the United Kingdom?s EU membership, the author aims to depict the continued British resistance towards EU integration deepening. The author analyzes the hesitance towards the deepening of British-European relations through various examples, such as the two referendums on continued EU membership, various opt-outs, and the European agendas of various British governments. The paper also shows that despite skepticism towards integration deepening, the UK was constantly inclined towards EU enlargement, in part as a reflection of the security-defense logic of its transatlantic priorities. The author intends to demonstrate that British politicians have been using numerous political, economical or social challenges during the past decade in order to secure growingly Eurosceptic votes. However, such narratives have resulted not only in greater support for Brexit but have also contributed to the political, identity, regional and other polarization. The above-mentioned facts lead to a twofold conclusion: by withdrawing from the EU, the country not only loses its special status, which used to constitute an important part of the British international role and identity, but also devolves mutual relations and fills them with distrust. Likewise, the author explains that the designing of sustainable and deepened transatlantic relations in the short-term is not particularly realistic, due to isolationist and unilateral tendencies of the current American administration. As part of the scientific explanation, the author uses the concepts of realist theories and intergovernmental approach. For the purpose of an additional illustration of the UK?s resistance towards integration deepening, the author employs the idea of British exceptionalism as a constant political phenomenon.

POLITISASI HIJAB KONTESTASI PEMILIHAN KEPALA DAERAH

&lt;p&gt;&lt;em&gt;This research about the transformation of &lt;/em&gt;&lt;em&gt;h&lt;/em&gt;&lt;em&gt;ijab women candidates in the political stage direct election of the regional head (Pilkada). In Indonesia hijab experienced a transformative instrument motif. This is related to the dynamics of democratization in Indonesia, the factor of political identity and religious polarization is very strong. The focus of this study is the motive &lt;/em&gt;&lt;em&gt;of wearing a hijab on women's candidates influenced various aspects including religion, fashion trend, even political interests to gain power. The theoretical study uses the &lt;/em&gt;&lt;em&gt;rational action&lt;/em&gt;&lt;em&gt; theory approach is the front stage and backstage. The object of this research is women candidates who suddenly use the hijab before the election of the regional head. &lt;/em&gt;&lt;em&gt;The purpose of this study to determine the motives behind the use of hijab, the objective of political parties to bring women candidates wearing hijab to gain sympathy and captivate the voice of Muslim voters.&lt;/em&gt;&lt;em&gt; The research method is a textual analysis on the use of Hijab. The results are expected with the emergence of women candidates who have hijab in direct local elections (Pilkada) bringing blessings and benefits, not just playing masks on the political stage as a means of winning&lt;/em&gt;&lt;em&gt; &lt;/em&gt;&lt;em&gt;and power for personal and group interests. &lt;/em&gt;&lt;/p&gt;

Segregation and properties at curved vs straight (000) inversion boundaries in piezotronic ZnO bicrystals

AbstractTEM and SEM investigations of ZnO bicrystal interfaces were undertaken with an aim to study the correlation of local grain‐boundary structure, segregation, and electrical transport perpendicular to the interface. To this end, varistor‐like ZnO bicrystals with piezotronic characteristics were chosen with (000)║(000) tail‐to‐tail orientation with respect to the c‐axis. In order to contrast different local grain‐boundary structures with different coherency and segregation of bismuth, but identical macroscopic polarization state, two complementary processing techniques were applied. A diffusion‐bonded bicrystal with an intermediate thin film containing Zn–Bi–Co–O provided a straight interface as reference. In contrast, a ZnO bicrystal prepared by epitaxial solid‐state transformation was manufactured by bonding two ZnO single crystals with a 100 µm thick polycrystalline ZnO varistor material with a typical dopant composition including bismuth and cobalt. This structure was annealed to the point that a bicrystal was formed with the varistor concentration at the boundary, which was strongly curved due to the polycrystalline microstructure still providing a shadow image at the interface. The results highlight a distinct correlation between local interfacial morphology, degree of segregation of bismuth, and degree of nonlinearity of the electrical transport across the interface.

All-Around Beam Switched Antenna With Dual Polarization for Drone Communications

This communication presents a drone-to-drone adaptive beam switched antenna with 360° beam coverage and dual polarizations. The proposed antenna maintains the all-around beam coverage with high directivity based on 16 concentric planar Yagi-Uda dipole array. The high gain dipole array beams are configured by eight vertical polarization elements and eight horizontal polarization elements with directors and reflectors. Depending on various communication environments, a single beam, multiple beams with identical polarization, or multiple beams with different polarizations can be adaptively controlled for highly reliable drone-to-drone communication. To ensure the compactness in the antenna array, 16 concentric planar antenna elements are arranged in an orthogonally crossed manner with optimized vertical and horizontal transition matching circuits. Each Yagi-Uda dipole element for vertical or horizontal polarization showed a measured peak gain of 6.35 and 6.40 dBi at 5.5 GHz, respectively. The proposed antenna was integrated with sub-6 GHz transceiver and microcontroller unit (MCU) to verify the switched beam performance with dual polarization. Also, the Tx and Rx operation at random beam conditions was tested by using two proposed antennas and showed an excellent performance from 5 to 6 GHz.

All-fiber multiplexing of vortex beams carrying orbital angular momentum (OAM) through a two-mode-selective coupler and a ring-core-fiber-polarization controller

To improve channel capacity, a novel concept of orbital angular momentum (OAM) multiplexing by a two-mode-selective coupler and a ring-core-fiber- polarization controller (RCFPC) is proposed. A ring-core fiber (RCF) with larger mode-separation degrees between adjacent vector modes is also designed and fabricated, which can support the first-and second-order vector/OAM beams propagations. The TMSC comprised of two SMFs and the RCF is manufactured and used to convert HE11 in two single-mode fibers (SMFs) into the HE21/HE31 mode in the RCF. The RCFPC is used to adjust the phase differences between the even and odd modes of HE21/HE31 for generating and multiplexing OAM modes (topological charge = 1 and 2) with left/right-circle polarization in an all-fiber system. To verify the feasibility of the proposed concept, a new experimental platform is also designed and established. The measured results are consistent with the simulation results overall, and then also demonstrate that the proposed concept is correct in theory and practice. In addition, bit error rate and constellation graph are also investigated to evaluate the influences of some parameters and multiplexing ways on the system performances. The results also demonstrate that the system performances decline with the increases of RCF length and wavelength. In addition, compared to the case of only one OAM mode propagation, the system performances significantly decrease when OAM modes are multiplexed. The measured powers of OAM modes in the receiver are also employed to analyze the crosstalk distribution among different OAM modes. The suffered crosstalk of an OAM mode with less topological charge is less than another OAM mode with a larger topological charge. The crosstalk between two OAM beams with identical polarization is larger than the crosstalk between two OAM beams with different polarization.

Kinetics of a Collision-Induced Photon Echo

The nonmonotonic kinetics of a collision-induced photon echo has been investigated for a number of buffer atoms. The collision-induced photon echo was generated at the 174Yb (6s2) 1S0 ↔ (6s6p) 3P1 (0 ↔ 1) transition by a pair of linearly and mutually orthogonally polarized resonant radiation pulses in ytterbium vapor and its mixtures with He, Ne, Ar, Kr, and Xe. The kinetics of the conventional photon echo generated by pulses with identical linear polarizations was recorded in the same mixtures. The derived decay rate constants for both types of echo are equal to within the measurement errors. For the collisions of 174Yb atoms between themselves and with other ytterbium isotopes in a natural mixture of isotopes, an upper limit for the anisotropy parameter has been estimated, 0.22 ± 0.07 of the photon echo signal decay rate.