Coherent THz imaging using the self-mixing effect in quantum cascade lasers
نویسندگان
چکیده
We demonstrate that the self-mixing effect in terahertz frequency quantum cascade lasers can be used for three-dimensional coherent imaging; swept-frequency interferometry for imaging and materials analysis; and, high-resolution inverse synthetic aperture radar imaging. OCIS codes: (110.6795) Terahertz imaging; (140.5965) Semiconductor lasers, quantum cascade
منابع مشابه
Temperature Effect on THz Quantum Cascade Lasers
A simple semi-phenomenological model, which accurately predicts the dependence of thresholdcurrent for temperature of Resonant-phonon three well quantum cascade laser based on verticaltransitions is offered. We found that, the longitude optical phonon scattering of thermally excitedelectrons is the most important limiting factor for thermal performance of high frequency THz QCLs.In low frequenc...
متن کاملTerahertz imaging through self-mixing in a quantum cascade laser.
We demonstrate terahertz (THz) frequency imaging using a single quantum cascade laser (QCL) device for both generation and sensing of THz radiation. Detection is achieved by utilizing the effect of self-mixing in the THz QCL, and, specifically, by monitoring perturbations to the voltage across the QCL, induced by light reflected from an external object back into the laser cavity. Self-mixing im...
متن کاملDesign Optimization for 4.1-THZ Quantum Cascade Lasers
We present an optimized design for GaAs/AlGaAs quantum cascade lasers operating at 4.1THz. This was based on a three-well active module with diagonal radiative transition. This was performed by modifying the existing model structure, to reduce the parasitic anticrossings (leakage currents) as well as the optical gain linewidth. While the gain FWHM was reduced by more than 50% the gain pea...
متن کاملActive phase-nulling of the self-mixing phase in a terahertz frequency quantum cascade laser.
We demonstrate an active phase-nulling scheme for terahertz (THz) frequency quantum cascade lasers (QCLs) under optical feedback, by active electronic feedback control of the emission frequency. Using this scheme, the frequency tuning rate of a THz QCL is characterized, with significantly reduced experimental complexity compared to alternative approaches. Furthermore, we demonstrate real-time d...
متن کاملOrigin of terminal voltage variations due to self-mixing in terahertz frequency quantum cascade lasers.
We explain the origin of voltage variations due to self-mixing in a terahertz (THz) frequency quantum cascade laser (QCL) using an extended density matrix (DM) approach. Our DM model allows calculation of both the current-voltage (I-V) and optical power characteristics of the QCL under optical feedback by changing the cavity loss, to which the gain of the active region is clamped. The variation...
متن کامل