We propose an experimental scheme to realize a nanoheat engine with a single ion. An Otto cycle may be implemented by confining the ion in a linear Paul trap with tapered geometry and coupling it to engineered laser reservoirs. The quantum efficiency at maximum power is analytically determined in various regimes. Moreover, Monte Carlo simulations of the engine are performed that demonstrate its...

in order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. to do this we have investigated optical waveguide both with and without optical pumping. the rate of absorption and emission using an array of algaas/gaas quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. by con...

This Letter investigates the efficiency enhancement achieved by tunnel junction insertion into the InGaN/GaN multi-quantum well (MQW) active region of blue light emitting diodes (LEDs). The peak quantum efficiency of such LED exceeds 100%, but the maximum wall-plug efficiency (WPE) hardly changes. However, due to the increased bias, the WPE peaks at much higher input power, i.e., the WPE droop ...

Water soluble CdSe/ZnS nanoparticles with emission maxima from 511 nm to 596 nm and quantum efficiencies ranging from 11% to 28% are synthesized in a facile two-step method in ambient atmospheric conditions using a commercially available microwave reactor.

20 nm ZnO nanoparticles are used to fabricate the mesoporous photoanode of the CdS/CdSe quantum dot-sensitized solar cells by the simple doctor blade method. A maximum power conversion efficiency of 4.46% has been achieved, which indicated exciting prospects for ZnO nanoparticle based quantum dot-sensitized solar cells.

Quantum dot (QD) solar cells have the potential to increase the maximum attainable thermodynamic conversion efficiency of solar photon conversion up to about 66% by utilizing hot photogenerated carriers to produce higher photovoltages or higher photocurrents. Three quantum dot solar cell configurations are described.

In this work, the performance of a 640 512 long-wavelength resonant quantum well infrared photodetector (R-QWIP) focal plane array (FPA) was evaluated as a function of operating temperature, bias, and photon flux using an F/2.2 optic. From these FPA measurements an assessment of the dark current, noise, conversion efficiency and noise-equivalent temperature difference is provided herein. Histog...

An efficient mid-infrared frequency comb source is of great interest to high speed, high resolution spectroscopy and metrology. Here we demonstrate a mid-IR quantum cascade laser frequency comb with a high power output and narrow beatnote linewidth at room temperature. The active region was designed with a strong-coupling between the injector and the upper lasing level for high internal quantum...

Ultrafast, high-efficiency single-photon detectors are among the most sought-after elements in modern quantum optics and quantum communication. However, imperfect modal matching and finite photon absorption rates have usually limited their maximum attainable detection efficiency. Here we demonstrate superconducting nanowire detectors atop nanophotonic waveguides, which enable a drastic increase...