相关论文: Thermoelectrically cooled THz quantum cascade lase…
High peak and average power free-electron lasers (FELs) in the terahertz region (THz) require small diameter, low-emittance, and high voltage electron beams. This paper presents two 1.5-2 MV, 100-200 A, thermionic cathode electron source…
Experimental tests of gravity's fundamental nature call for mechanical systems in the quantum regime while being sensitive to gravity. Torsion pendula, historically vital in studies of classical gravity, are ideal for extending…
Stable ultrashort light pulses and frequency combs generated by mode-locked lasers have many important applications including high-resolution spectroscopy, fast chemical detection and identification, studies of ultrafast processes, and…
The Terahertz frequency range bears intriguing opportunities, beyond very advanced applications in spectroscopy and matter control. Peculiar quantum phenomena are predicted to lead to light emission by non-trivial mechanisms. Typically,…
We obtained an optical-to-terahertz (THz) energy conversion efficiency of 0.5% using the tilted-pulse-front technique in lithium niobate at a cryogenically cooled temperature of 100 K pumped by amplified Ti:sapphire laser pulses with ~150…
Preparing and manipulating quantum states of mechanical resonators is a highly interdisciplinary undertaking that now receives enormous interest for its far-reaching potential in fundamental and applied science. Up to now, only nanoscale…
We identify the operational conditions for maximum power of a nanothermoelectric engine consisting of a single quantum level embedded between two leads at different temperatures and chemical potentials. The corresponding thermodynamic…
Reducing the thermal noises in microwave (MW) resonators can bring about significant progress in many research fields. In this study, we consider using three-level or four-level systems as "quantum refrigerators" to cool down MW resonators…
Collective vibrations of proteins, rotations of small molecules, excitations of high-temperature superconductors, and electronic transitions in semiconductor nanostructures occur with characteristic frequencies between 1 and 10 THz.…
The design and operation of an electronic cooler based on a combination of superconducting tunnel junctions is described. The cascade extraction of hot-quasiparticles, which stems from the energy gaps of two different superconductors,…
We analyze the dynamics of atom-laser interactions for atoms having multiple, closely spaced, excited-state hyperfine manifolds. The system is treated fully quantum mechanically, including the atom's center-of-mass degree of freedom, and…
We demonstrate millikelvin thermometry of laser cooled trapped ions with high-resolution imaging. This equilibrium approach is independent of the cooling dynamics and has lower systematic error than Doppler thermometry, with \pm5 mK…
We propose and substantiate the concept of terahertz (THz) laser enabled by the resonant electron radiative transitions between graphene layers (GLs) in double-GL structures. We estimate the THz gain for TM-mode exhibiting very low Drude…
We present GaSb-based interband cascade lasers emitting at a center wavelength of 6.12 $\mu$m at 20$^\circ$C in continuous-wave operation up to a maximum operating temperature of 40$^\circ$C. Pulsed measurements based on broad area devices…
We introduce a scheme for deep laser cooling of molecules based on robust dark states at zero velocity. By simulating this scheme, we show it to be a widely applicable method that can reach the recoil limit or below. We demonstrate and…
The collective Raman cooling of a trapped two-component Fermi gas is analyzed. We develop the quantum master equation that describes the collisions and the laser cooling, in the festina lente regime, where the heating due to photon…
Quantum cascade lasers (QCLs) represent a fascinating accomplishment of quantum engineering and enable the direct generation of terahertz (THz) frequency radiation from an electrically-biased semiconductor heterostructure. Their large…
We report room temperature heterodyne detection of a quantum cascade laser beaten with a local oscillator on a unipolar quantum photodetector in two different atmospheric windows, at 4.8 $\mu$m and 9 $\mu$m. A noise equivalent power of few…
The possibility of using quantum Hall systems for thermoelectric energy conversion is investigated. It is shown that the massive degeneracy and the metallicity of a partially-filled Landau level enable thermoelectric cooling and power…
The scaling of the optimal cooling power of a reciprocating quantum refrigerator is sought as a function of the cold bath temperature as $T_c \to 0$. The working medium consists of noninteracting particles in a harmonic potential. Two…