High Mechanical Quality Factor Research Articles

High mechanical quality factor and high piezoelectric coefficient achieved via acceptor-modified invisible boundary

High mechanical quality factor (Qm) and high piezoelectric coefficient (d33) are desired for high-power applications of piezoelectric ceramics. However, achieving them based on currently known mechanisms has proven challenging because of the tradeoff between Qm and d33. Here we report a surprising finding that this tradeoff can be overcome via acceptor-modified invisible-boundary (IB). High Qm ∼1096 and high d33 ∼337 pC/N were achieved and superior to those of both lead-free and commercial lead-based piezoceramics. The acceptor-modified IB was demonstrated in Fe-doped BaTi0.89Hf0.11O3 ceramics, where the acceptor doping in the IB composition increases Qm by ∼8.6 times and d33 by ∼1.5 times, being different from the acceptor doping effect in morphotropic/polymorphic phase boundary (MPB/PPB) compositions of increasing Qm but decreasing d33. We predict that our finding may also be made in other acceptor-modified IB systems and the obtained high-performance BaTiO3-based piezoceramic could provide an alternative to lead-based piezoceramics in underwater applications.

Characterization of temperature-dependent full-matrix constants of [001]c-poled Mn-doped 28PIN-43PMN-29PT single crystals using one sample

[001]c-poled Mn-doped xPb(In1/2Nb1/2)O3–(1–x–y)Pb(Mg1/3Nb2/3)O3–yPbTiO3 (PIN–PMN–PT:Mn) single crystals (SCs) in the rhombohedral phase possess not only excellent piezoelectric properties but also a high mechanical quality factor, which make them suitable for fabricating high-performance piezoelectric devices. Characterizing the temperature dependence (TD) of full-matrix constants is indispensable for their use in device design. However, there is a significant lack of relevant data. In this study, the TD of the clamped dielectric properties of [001]c-poled 28PIN-43PMN-29PT:Mn SCs was characterized using a dielectric temperature spectroscopy measurement system from 0 to 60 °C. Their elastic and piezoelectric constants were measured using resonant ultrasound spectroscopy in the same temperature range. With an increase in the temperature, all the elastic stiffness constants decreased, whereas all the clamped dielectric constants and the absolute values of all the piezoelectric stress constants increased. The characterization process required only a single sample, which ensured the consistency of the results. Furthermore, the electrical impedance spectra of the sample at 30 and 50 °C were measured and compared with those simulated using the finite-element method with the characterization results. The close agreement between them confirmed the reliability of the characterization results.

Enhancing the piezoelectric performance of novel PZT-PMS-PSN piezoelectric ceramics by fine-tuning the monoclinic phase

The enhanced high-power performance of 0.93 Pb(Zr1-xTix)O3-0.05 Pb(Mn1/3Sb2/3)O3-0.02 Pb(Sc1/2Nb1/2)O3 (x = 0.48, 0.50, 0.52, 0.54, 0.56) piezoelectric ceramics (PZT-PMS-PSN) has been achieved with notable improvement in the piezoelectric coefficient (d33). The presence of the monoclinic phase (Cc) has led to an increase in d33 from 214 pC N−1 to 315 pC N−1. Therefore, the composition 0.93 Pb(Zr0.48Ti0.52)O3-0.05 Pb(Mn1/3Sb2/3)O3-0.02 Pb(Sc1/2Nb1/2)O3 exhibits excellent mechanical and electrical parameters: a d33 value of 315 pC N−1, a high mechanical quality factor of 1578, an electromechanical coupling factor kp of 52 %, and a low dielectric loss tanδ of only 0.288 %. Additionally, this ceramic exhibits a significantly high Curie temperature (Tc), reaching up to 328 °C which stabilizes its ferroelectric phase. Moreover, the phase transition of PZT-PMS-PSN ceramics from rhombohedral to tetragonal phase was investigated by X-ray diffraction, Raman scattering, Piezo-response force microscopy.

Enhancement of Brillouin nonlinearities with a coupled resonator optical waveguide.

Stimulated Brillouin scattering (SBS) is a nonlinear optical phenomenon mediated from the coupling of photons and phonons. It has found applications in various realms, yet the acousto-optic interaction strength remains relatively weak. Enhancing the SBS with resonant structures could be a promising solution, but this method faces strict constraints in operational bandwidth. Here, we present the first demonstration to our knowledge of the broadband enhancement of Brillouin nonlinearities by a suspended coupled resonator optical waveguide (CROW) on an SOI platform. By comprehensively balancing the Brillouin gain and operational bandwidth, a 3-fold enhancement for the Brillouin gain coefficient (GB) and a broad operational bandwidth of over 80 GHz have been achieved. Furthermore, this 1.1 mm device shows a forward Brillouin gain coefficient of 2422 m-1W-1 and a high mechanical quality factor (Qm) of 1060. This approach marks a pivotal advancement toward wide bandwidth, low energy consumption, and compact integrated nonlinear photonic devices, with potential applications in tunable microwave photonic filters and phonon-based non-reciprocal devices.

Quaternary piezoelectric ceramics with ultra-high mechanical quality factor

The development of piezoelectric ceramics with large piezoelectric coefficient (d33), high Curie temperature (TC) and high mechanical quality factor (Qm) is still a key challenge for practical application for high-power device. Herein, a novel quaternary piezoelectric ceramics of (0.125-x) Pb0.98Sr0.02(Mg1/3Nb2/3)O3–0.445PbTiO3–0.43PbZrO3-xPb(Mn1/3Nb2/3)O3 (abbreviated as xPMnN-PSMN-PZT) were prepared by the solid-state sintering method. The hard dopant PMnN induced the morphotropic phase boundary (MPB) of PSMN-PZT into a tetragonal-rich region. In addition, the XPS and EPR analysis proved the existence of a large amount of oxygen vacancies (Vo••) in PMnN-PSMN-PZT ceramic system. The composition near tetragonal-rich MPB region and the appearance of defect dipoles formed a strong coupling effect on the domain wall motion and leaded to an ultra Qm value. The optimum piezoelectric properties were achieved at x = 9 mol% with d33 = 260 pC/N, Qm = 3880, tanδ = 0.009 and TC = 332 °C. A significant internal bias field (Ebias) of 8.83 kV/cm was also observed in 0.09PMnN-PSMN-PZT ceramics. The origin of this excellent piezoelectric properties was explained by the phase structure, piezoelectric and dielectric analysis. This work demonstrated a rational strategy to obtain ultra Qm value for high-power piezoceramics.

Improved piezoelectric and photoluminescence properties in Ce-doped PSN-PMN-PT piezoelectric ceramics by multiscale coordination

The large piezoelectric coefficient (d33) and high mechanical quality factor (Qm) are essential for piezoelectric ceramics used in high-power devices. It is pity that the two parameters are usually opposite, with higher d33 corresponding to lower Qm. In order to well-balance the d33 and Qm, the rare-earth element Ce with multi-valence was introduced into the 0.06 Pb(Sc1/2Nb1/2)O3-0.61 Pb(Mg1/3Nb2/3)O3-0.33PbTiO3 (xCe-PSN-PMN-PT) ceramics in this work. The structure, electrical properties and optical properties of ceramics were systematically analyzed. Optimal electrical performances (d33 = 719 pC/N, Qm = 256, and dielectric loss tanδ = 0.007) were obtained in 0.02Ce-PSN-PMN-PT ceramics. These excellent performances originate from the multiscale coordination effects among defect dipoles, local structural heterogeneity, domain structure, phase structure, and grain size. The xCe-PSN-PMN-PT ceramics exhibit excellent photoluminescence properties in the blue wavelength range. Our research provides a new paradigm for deep-sea electro-optical communication.

Slow-light-enhanced Brillouin scattering with integrated Bragg grating.

Advancements in photonic integration technology have enabled the effective excitation of simulated Brillouin scattering (SBS) on a single chip, boosting Brillouin-based applications such as microwave photonic signal processing, narrow-linewidth lasers, and optical sensing. However, on-chip circuits still require large pump power and centimeter-scale waveguide length to achieve a considerable Brillouin gain, making them both power-inefficient and challenging for integration. Here, we exploit the slow-light effect to significantly enhance SBS, presenting the first, to the best of our knowledge, demonstration of a slow-light Brillouin-active waveguide on the silicon-on-insulator (SOI) platform. By integrating a Bragg grating with a suspended ridge waveguide, a 2.1-fold enhancement of the forward Brillouin gain coefficient is observed in a 1.25 mm device. Furthermore, this device shows a Brillouin gain coefficient of 1,693 m-1W-1 and a mechanical quality factor of 1,080. The short waveguide length reduces susceptibility to inhomogeneous broadening, enabling the simultaneous achievement of a high Brillouin gain coefficient and a high mechanical quality factor. This approach introduces an additional dimension to enhance acousto-optic interaction efficiency in the SOI platform and holds significant potential for microwave photonic filters and high spatial resolution sensing.

Modified Pb(Mg1/3Nb2/3)O3-PbZrO3-PbTiO3 ceramics with high d33，large Qm and high Tc

The development of piezoelectric ceramics with large piezoelectric coefficient (d33), high Curie temperature (Tc) and high mechanical quality factor (Qm) is still a key challenge for practical application for high-power device. Herein, a series of Sm3+ and Mn2+ ions co-doped 0.15Pb(Mg1/3Nb2/3)O3-(0.85-x)PbZrO3-xPbTiO3 ceramics were prepared by the solid-state sintering method. The optimum piezoelectric properties were achieved at x = 0.435 mol% with a large d33 ∼ 450 pC/N and a high Qm ∼ 1968 near the morphotropic phase boundary (MPB), and with high Tc ∼ 296 °C. The origin of this excellent piezoelectric properties was explained by the phase structure, piezoelectric and dielectric analysis. The composition near MPB region and the appearance of defect dipoles leaded to final excellent piezoelectric properties, and made a harmonization between d33, Tc and Qm. This work demonstrated a rational strategy to obtain large d33, high Tc and high Qm for high-power piezoceramics.

Enhancing the piezoelectric properties and thermal stability of PMN-PMS-PSZT high-power piezoelectric ceramics through defect engineering

The development of high-power piezoelectric ceramics with superior piezoelectric properties and broad temperature usage ranges is vital for the thriving progress of electromechanical applications. However, achieving high piezoelectricity, high mechanical quality factor, and temperature stability often presents a trade-off. In this study, we present an advanced ceramic material with excellent high-power piezoelectric properties and superior temperature stability. The piezoelectric coefficient d33 reaches 348 pC N−1, the electromechanical coupling factor kp is 54%, the mechanical quality factor Qm is 1501, the dielectric loss tanδ is 0.35%, and the d33 variation is less than 10% within 25–210 °C in 0.05Pb(Mg1/3Nb2/3)O3-0.05Pb(Mn1/3Sb2/3)O3-0.9Pb0.95Sr0.05(Zr0.48Ti0.52)O3 ceramic. The excellent piezoelectricity is attributed to the enhancement of intrinsic ionic displacement and reversible domains wall motion because of symmetry-conforming short-range distribution of oxygen vacancy, while the high Qm is a result of increased domain size and oxygen vacancy. The outstanding temperature stability is related to the stable non-180°domains structure due to the oxygen vacancy pinning effect. These properties hold great potential for advanced applications, particularly for piezoelectric high-power applications requiring constant d33 over a broad temperature range.

Precise evaluation of the material constants of [011]-poled mangan-doped 0.32Pb(In1/2Nb1/2)O3-0.39Pb(Mg1/3Nb2/3)O3-0.29PbTiO3 single crystals

Recently, there has been a surge of interest in [011]-poled Mn: PIN-PMN-PT piezoelectric single crystals for high-power transducers. These crystals boast impressive electromechanical coupling coefficients, piezoelectric constants in the transverse mode, and excellent heat resistance due to their high mechanical quality factor. To effectively design transducers using these crystals, understanding their material constants is crucial. Our study focused on determining these constants by employing the resonance method. We created eleven different resonators, analyzed their impedance spectra, and derived seventeen elastic compliance, piezoelectric, and dielectric constants. The precision of the obtained material constants was enhanced by minimizing the difference between the impedance spectra found through finite element analyses and actual measurements of each resonator. The accuracy of these derived constants was validated by comparing the impedance spectra obtained from analysis with those measured experimentally. This novel approach demonstrated a capability to derive more precise material constants than prior studies. These refined material constants hold the potential to enable more precise and effective design of acoustic transducers constructed from the single crystals.

Enhanced high-power behaviors of Mn-doped Pb (In1/2Nb1/2) O3-Pb(Mg1/3Nb2/3) O3-PbTiO3 piezoelectric crystals through combining direct and alternating current polarization

Elevating both the mechanical quality factor and piezoelectric properties is pivotal for enhancing the efficiency of high-power piezoelectric devices. Mn-doped Pb (In1/2Nb1/2) O3-Pb(Mg1/3Nb2/3) O3-PbTiO3 (Mn: PIN-PMN-PT) single crystals have previously exhibited a notable mechanical quality factor, yet encountered a substantial decline in piezoelectric coefficient. In pursuit of the concurrent optimization of these parameters, we explored the co-enhancement of mechanical quality factor and piezoelectric coefficient in [001]-oriented Mn: PIN-PMN-PT single crystals by employing a synergistic approach (DCP-ACP) involving direct-current poling (DCP) and alternating-current poling (ACP). Our investigation reveals a remarkable improvement, with the piezoelectric coefficient and mechanical quality factor experiencing a notable surge of 53% and 118%, respectively, compared to the outcomes achieved with DCP alone. Compared to the ACP method, the piezoelectric coefficient and the mechanical quality factor were improved more than 7% and 18%, respectively. Moreover, the coercive field and remnant polarization of the single crystals witnessed a substantial upswing post DCP-ACP. The results are attributed to the elimination of the 71° domain walls, as observed through polarized light microscopy. Here we demonstrate Mn: PIN-PMN-PT single crystals are expected to has high mechanical quality factor and strong piezoelectric constants through DCP-ACP, thus suggesting a new route to high performance ferroelectrics.

Well-balanced performance achieved in PZT piezoceramics via a multiscale regulation strategy.

Emerging high-power piezoelectric applications demand the development of piezoelectric materials featuring both a high mechanical quality factor (Qm) and a large piezoelectric coefficient (d33). However, it is widely accepted that an increase in d33 is usually accompanied with a decrease in Qm, and vice versa. Herein, a multiscale regulation strategy is proposed to improve Qm and d33 simultaneously from the perspectives of phase structure, ferroelectric domains, and lattice defects. A well-balanced combination of electromechanical performances with Qm = 726, d33 = 502 pC N-1, kp = 0.69, tan δ = 0.0024, and TC = 267 °C was obtained. Through structural characterization, it was observed that the morphotropic phase boundary and enhanced dispersion behavior lead to a lowered energy barrier, which contributes to polarization rotation and enhances piezoelectric performance. At the same time, the excellent piezoelectric performances also benefit from the highly oriented domain structure and small domain size after high-temperature poling. Furthermore, the segregation of Ba2+ causes A-site defects in the crystal lattice, accompanied with an increase in oxygen vacancies, which maintains the hardening effect of the ceramics. This study proposes a multiscale regulation strategy, providing insights for the design of high-power piezoelectric ceramics with high d33 and Qm.

Origin of high comprehensive electromechanical properties of novel donor and acceptor–codoped PMN–30PT ceramics

Donor and acceptor–codoped PMN–30PT ceramics with 1–3 mol% Sm and 1 mol% Mn were fabricated via a two-step solid-state reaction. The crystal structure and electrical properties were investigated in detail. Donor Sm and acceptor Mn codoping substantially enhances the electromechanical, piezoelectric, and dielectric properties with a high piezoelectric coefficient d33 = 483–680 pC/N, a high mechanical quality factor Qm = 518–642, a high field-induced strain = 0.20%–0.24 %, and a low dielectric loss tan δ = 0.54%–0.69 %. X-ray diffraction and Raman spectra reveal the coexisting triple phase composition of the rhombohedral phase, tetragonal phase, and monoclinic polar nanoregions. Thermally stimulated depolarization current verifies the formation of various defect dipole clusters such as (MnTi″–VO··)×. With enhanced local structure heterogeneity induced by Sm, the phase composition and defect chemistry are regarded as the origin of such high comprehensive performance.

Defect engineering in barium titanate ferroelectric ceramic showing simultaneous enhancement of piezoelectric coefficient and mechanical quality factor

For high-power on-resonant piezoelectric applications, piezoelectric materials with high piezoelectric coefficient (d33) and mechanical quality factor (Qm) are in high demand. However, previous work has shown that the d33 and Qm are generally inversely proportional, implying that it is difficult to improve these properties simultaneously. Here we report the simultaneous enhancement of d33 and Qm in (Mn, Zr) co-doped BaTiO3 (BT-xMn-yZr) ceramics. Compared with pure BaTiO3 ceramics, the piezoelectric coefficient (d33) of BT-0.5%Mn-5%Zr ceramic is increased from 190 pC/N to 321 pC/N, and the Qm is increased from 290 to 513. Furthermore, the Qm of BT-1%Mn-5%Zr ceramic reaches 1470, and the d33 is 248 pC/N. When both d33 and Qm are considered, the obtained properties outperform commercial hard Pb(Zr,Ti)O3 and other typical lead-free ferroelectric ceramics. The experimental results show that the enhanced d33 and Qm of these ceramics originate from the synergistic effect of defect engineering-induced domain configuration effect and pinning effect. This work provides insights into the design of high-performance high-power lead-free ferroelectric materials.

Achieving combinatory “soft” and “hard” piezoelectric properties in textured ceramics via exploring single‐crystal‐like electrostriction

AbstractDesign of a projecting‐receiving dual‐purpose transducer is challenging due to the difficulty of synthesizing piezoelectric materials with combinatory “soft” properties (high piezoelectric coefficient d) and “hard” properties (low dielectric loss and high mechanical quality factor Qm). In this study, we provide a different perspective to address this challenge via exploiting single‐crystal‐like electrostriction coefficient Q33 through the fabrication of grain oriented or textured “hard” piezoelectric ceramics. Mn‐doped 0.27Pb(In1/2Nb1/2)O3–0.41Pb(Mg1/3Nb2/3)O3–0.32PbTiO3 (Mn:PIN–PMN–PT) piezoelectric ceramics with a high [0 0 1]c texture fraction of 99% were synthesized, which exhibit three times greater piezoelectric properties (d33 ∼ 828 pC/N) than random counterparts (d33 ∼ 251 pC/N), while maintaining low loss (tan δ ∼ 0.5%, Qm = 443). According to the formula , the large improvement of d33 in textured ceramics is mainly due to a doubling increase in dielectric constant ε33 and Q33 (∼0.057 m4/C2). Notably, the Q33 exhibits remarkable similarity to that of PMN–PT single crystals, further contributing to the enhanced piezoelectric performance of textured ceramics. Phase field model of ferroelectrics was performed to understand the texturing on Q33 and elucidate the underlying mechanism at the domain level. The textured ceramics exhibit excellent combinatory “soft” and “hard” properties, which are the promising materials for developing projecting‐receiving dual‐purpose transducers with high efficiency and high sensitivity.

Cavity Optomechanical Bistability with an Ultrahigh Reflectivity Photonic Crystal Membrane

AbstractPhotonic crystal (PhC) membranes patterned with sub‐wavelength periods offer a unique combination of high reflectivity, low mass, and high mechanical quality factor. Using a PhC membrane as one mirror of a Fabry–Perot cavity, a finesse as high as is demonstrated, corresponding to a record high PhC reflectivity of and an optical quality factor of . The fundamental mechanical frequency is 426 kHz, more than twice the optical linewidth, placing it firmly in the resolved‐sideband regime required for ground‐state optical cooling. The mechanical quality factor in vacuum is , allowing values of the single‐photon cooperativity as high as . Optomechanical bistability is easily observed as hysteresis in the cavity transmission. As the input power is raised well beyond the bistability threshold, dynamical backaction induces strong mechanical oscillation above 1 MHz, even in the presence of air damping. This platform will facilitate advances in optomechanics, precision sensing, and applications of optomechanically‐induced bistability.

Mn-doped 0.15Pb(Yb1/2Nb1/2)O3–0.48Pb(Mg1/3Nb2/3)O3–0.37PbTiO3 piezoelectric ceramics for high performance high-power transducers

For high-power transducer applications, the piezoelectric materials should fulfill specific requirements of a high mechanical quality factor (Qm), a high piezoelectric strain coefficient (dij), and a high Curie phase transition temperature (Tc). In this study, we present an investigation of the structural, piezoelectric, and high-power characteristics of Mn-doped 0.15Pb(Yb1/2Nb1/2)O3–0.48Pb(Mg1/3Nb2/3)O3–0.37PbTiO3 (0.15PYN–0.48PMN–0.37PT) ceramics. The introduction of Mn dopants led to an increase in the tetragonal phase fraction within the 0.15PYN–0.48PMN–0.37 PT ceramics and the formation of oxygen vacancies, consequently significantly enhancing Qm due to their synergistic effect. Despite the hardening effect, the high value of the piezoelectric coefficient (d33) was maintained due to the increase in grain size. Particularly, the specimen doped with 3 mol% of Mn exhibited excellent piezoelectric properties of d33 = 345 pC/N, Qm = 1159, and Tc = 207°C. This specimen displayed a high vibration velocity of 0.6 m/s under the condition of equilibrium ΔT < 20°C (temperature rise from initial temperature), thereby confirming its immense potential for high-power transducer applications.

Poling above the Curie temperature driven large enhancement in piezoelectric performance of Mn doped PZT-based piezoceramics

The enhancement of piezoelectricity is usually in sacrifice of Curie temperature, which in turn limits its working temperature range. It is well known that there are some trade-off among the various performance parameters of most piezoelectric ceramics, and it is still difficult to achieve synergistic improvement in multiple parameters. Here, it is reported that the piezoelectric coefficient d33 of a 0.6 mol% Mn-doped Pb(Sb0.5Nb0.5)0.02Zr0.51Ti0.47O3 piezoelectric ceramics is increased to 436 pC N−1, and its electro-strain can reach 0.16% (d33* = 800 pm/V) at 2 kV mm− 1 by high-temperature poling, whose Curie temperature can still keep at 347 ℃. The features of "hard" piezoelectric ceramics such as low dielectric loss (tgδ = 0.23%) and high mechanical quality factor (Qm = 546) are also preserved. Through structural characterization, combined with the theoretical results of phase field simulation, it is shown that its excellent piezoelectric performance originates from the highly oriented domain structure and small domain size after high temperature poling. On the other hand, the valence state transition of Mn3+ ions during high-temperature poling increases the defect vacancies and lattice distortion in ceramics, which keeps the acceptor-doped characteristic of the ceramics.

Demonstration of frequency stability limited by thermal fluctuation noise in silicon nitride nanomechanical resonators

The frequency stability of nanomechanical resonators (NMRs) dictates the performance level of many state-of-the-art sensors (e.g., mass, force, temperature, radiation) that relate an external physical perturbation to a resonance frequency shift. While this is obviously of fundamental importance, accurate models and understandings of sources of frequency instability are not always available. The contribution of thermomechanical noise to frequency stability has been well studied in recent years and is often the fundamental performance limitation. Frequency stability limited by thermal fluctuation noise has attracted less interest but is nevertheless of fundamental importance notably in temperature sensing applications. In particular, temperature-sensitive NMR have become promising candidates for replacing traditional bolometers in infrared radiation sensing. However, reaching the ultimate detectivity limit of thermal radiation sensors requires their noise to be dominated by fundamental thermal fluctuation, which has not been demonstrated to date. In this work, we first develop a theoretical model for computing the frequency stability of NMR by considering the effect of both additive phase noise (i.e., thermomechanical and experimental detection noise) and thermal fluctuation noise in a close-loop frequency tracking scheme. We thereafter validate this model experimentally and observe thermal fluctuation noise in SiN drum resonators of various sizes at room temperature. Our work shows that by using resonators of specific characteristics—such as high temperature sensitivity, high mechanical quality factors, and high mass-to-thermal-conductance ratio—one can minimize additive phase noise below thermal fluctuation noise. This paves the way for uncooled NMR-based radiation sensors that can reach the fundamental detectivity limit of thermal radiation sensing and outperform existing technologies.

Phononically shielded photonic-crystal mirror membranes for cavity quantum optomechanics.

We present a highly reflective, sub-wavelength-thick membrane resonator featuring high mechanical quality factor and discuss its applicability for cavity optomechanics. The 88.5 nm thin stoichiometric silicon-nitride membrane, designed and fabricated to combine 2D-photonic and phononic crystal patterns, reaches reflectivities up to 99.89 % and a mechanical quality factor of 2.9 × 107 at room temperature. We construct a Fabry-Perot-type optical cavity, with the membrane forming one terminating mirror. The optical beam shape in cavity transmission shows a stark deviation from a simple Gaussian mode-shape, consistent with theoretical predictions. We demonstrate optomechanical sideband cooling to mK-mode temperatures, starting from room temperature. At higher intracavity powers we observe an optomechanically induced optical bistability. The demonstrated device has potential to reach high cooperativities at low light levels desirable, for example, for optomechanical sensing and squeezing applications or fundamental studies in cavity quantum optomechanics; and meets the requirements for cooling to the quantum ground state of mechanical motion from room temperature.