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We study the effect of spin pair interactions in a chip-scale atomic clock of trapped 87Rb. These interactions can be used to inhibit dephasing in a cold atomic cloud. We also simulate the s-wave frequency shifts for fermions. These results are directly applicable to optical lattice clocks.
We have used the Pockels effect in ZnTe to demonstrate that the frequency and the phase of a 2.7Terahertz Quantum Cascade Laser can be actively stabilized to the n-th harmonic of the 90MHz repetition rate of a commercial, mode-locked Er-doped fiber-laser. The beating between the stabilized QCL frequency and the harmonic of the repetition rate yielded a signal-to-noise ratio of 80dB in 1Hz bandwidth...
We demonstrate the phase-locking of a 2.7Terahertz Quantum Cascade Laser to the repetition rate of a commercial Er-doped fiber-fs-laser. We observe a linewidth of the beatnote signal with a signal-to-noise of 80dB in 1Hz bandwidth.
Quantum Cascade Lasers (QCL) are probably the most promising sources for Terahertz wave generation. The key issue especially for double metal QCLs is the extraction and the beam shaping of the emitted power. We propose a solution with a TEM-Horn Antenna and we compare it to the most recently proposed solutions: plasmonic array, Silicon-lens etc. New Terahertz antenna designs will also be presented.
We report on the high frequency modulation of terahertz (THz) quantum cascade lasers (QCLs). By resonantly enhancing the frequency response of the RF biasing circuit we show that 4 mm and 1.5 mm-long metal-metal waveguide 2.3 THz QCLs, can be modulated up to 21 and 24 GHz respectively.
We demonstrate single-mode, surface-emitting terahertz lasers at lambdaap110 mum employing photonic-crystal resonators. The devices employ metal-metal waveguides, and the photonic-crystal lattice is implemented by the sole patterning of the top metal contact, without deep-etching the semiconductor in the photonic crystal holes. The device emission wavelength correctly tunes with the photonic crystal...
We demonstrate full control of the spectral and spatial emission properties of terahertz quantum cascade lasers using metallic photonic-crystals for lateral confinement. Single-mode, surface-emission is obtained at a frequency of 2.8-2.9 THz using a photonic-crystal design with a square lattice geometry. The resonator quality factor is then optimised, using a graded photonic-crystal architecture,...
We present the operation and the far field radiation pattern of a 2.9 THz double metal quantum cascade laser (QCL) with a micro TEM-horn antenna. An improvement of both the radiation pattern and the collected power level (typically a factor of 2 with f/1 optics) are observed in comparison with the QCL without antenna.
The authors introduced a new kind of Hamiltonian describing an infinite range coupling between particles placed on a square array with a large number of symmetries and describe its spectral properties. The authors also shows in particular that this Hamiltonian can be naturally realized using ions confined in a surface trap and that the induced protection is more effective than the one predicted for...
Quantum Cascade Lasers are one the most promising approach for the generation of THz waves and particularly in a double plasmon waveguide topology. Stripline resonators with a quasi-TEM mode are indeed interesting for THz-QCLs thanks to a high confinement factor combined with low losses. However they present two major drawbacks: the first is a poor outcoupling of the radiation, and the second is a...
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