Single Photonic Structure Research Articles

Reversible Switching of Strong Light-Matter Coupling Using Spin-Crossover Molecular Materials.

The formation of hybrid light-matter states through the resonant interaction of confined electromagnetic fields with matter excitations has emerged as a fascinating tool for controlling quantum-mechanical states and then manipulating the functionalities and chemical reactivity landscape of molecular materials. Here we report the first observation of switchable strong light-matter coupling involving bistable spin-crossover molecules. Spectroscopic measurements, supported by transfer-matrix and coupled-oscillator simulations, reveal Rabi splitting values of up to 550 meV, which at 15% of the molecular excitation energy enter the regime of ultrastrong coupling. We find that the thermally induced switching of molecules between their low-spin and high-spin states allows fine control of the light-matter hybridization strength, offering the appealing possibility of reversible switching between the ultrastrong- and weak-coupling regimes within a single photonic structure. Through this work, we show that spin-crossover molecular compounds constitute a promising class of active nanomaterials in the burgeoning context of tunable polaritonic devices and polaritonic chemistry.

Self-referenced hologram of a single photon beam

Quantitative characterization of the spatial structure of single photons is essential for free-space quantum communication and quantum imaging. We introduce an interferometric technique that enables the complete characterization of a two-dimensional probability amplitude of a single photon. Importantly, in contrast to methods that use a reference photon for the phase measurement, our technique relies on a single photon interfering with itself. Our setup comprises of a heralded single-photon source with an unknown spatial phase and a modified Mach-Zehnder interferometer with a spatial filter in one of its arms. The spatial filter removes the unknown spatial phase and the filtered beam interferes with the unaltered beam passing through the other arm of the interferometer. We experimentally confirm the feasibility of our technique by reconstructing the spatial phase of heralded single photons using the lowest order interference fringes. This technique can be applied to the characterization of arbitrary pure spatial states of single photons.

Generation of multiple signals using single photonic structure at visible regime: a proposal to realize the harmonic generation

Generation of multiple signals using single photonic structure at visible regime: a proposal to realize the harmonic generation

Three Ways Chip to Chip Communication via a Single Photonic Structure: A Future Paragon of 3D Photonics to Optical VLSI

A proposal is made in this paper to realize 3-ways chip to chip communication via 3D photonic structure. The mechanism of the work is understood with the help of absorbance and reflectance of the structure. The absorbance is determined using the analytical treatment where reflectance is computed using the photonic bandgap analysis, which is found with the help of plane wave expansion method. Further the present research deals with low power input signal whose potential varies from 0.55 to 1 V because to avoid the heat generation in nanoelectronics and nanophotonic circuits where circuit comprises chip, LED and photo detector along with waveguide (3D photonic structure). The output results indicate that a proper combination of lattice spacing of silicon-based 3D photonic structure and diameter of air holes could be a right candidate to realise 3-ways communication.

Realization of absorber, reflector and transmitter using single photonic structure

The present communication deals with a metamaterial based single photonic crystal fiber (PCF) to realize absorber, reflector, and transmitter application. The simulation studies which is made with the help of plane wave expansion method infers that the configuration including lattice spacing and diameter of air holes of the photonic crystal fiber along with the nature of the material play an important role to realize the aforementioned applications. Furthermore, the novelty of this work is that single PCF structure bestows absorber, reflector, and transmitter.

Managing photons for quantum information processing.

We study distinguishing information in the context of photonic quantum interference tailored for practical implementations of quantum information processing schemes. In particular, we consider the character of single-photon states optimized for multiple-source interference experiments and for experiments relying on Bell-state measurement and arrive at specific design criteria for photons produced by parametric down-conversion. Such states can be realistically implemented with available technology. We describe a novel method for characterizing the mode structure of single photons, and demonstrate it in the context of coherent light.