Print Email Facebook Twitter The Half-Josephson Laser: Essentials and Applications Title The Half-Josephson Laser: Essentials and Applications Author Godschalk, F. Contributor Nazarov, Y.V. (promotor) Faculty Applied Sciences Department Quantum nanoscience (theoretical physics) Date 2014-01-09 Abstract In this dissertation, we study a novel class of laser devices, referred to as half-Josephson lasers (HJL). Here, lasing at half the Josephson frequency is induced by a parametric instability, resulting from an oscillating supercurrent flowing through a Josephson junction that contains quantum emitters. The device combines the electronic coherence of superconductivity with the optical coherence of lasers, resulting in a phase lock between the optical phase and the superconducting phase difference across the junction. Apart from the introductory first chapter, this dissertation consists of two parts. In the first part, the essentials of HJL devices are investigated. First, we study a model containing a Josephson junction with a single quantum emitter. Spontaneous switchings in the quantum emitter lead to decoherence of the laser. After this, a general HJL model is derived for the case of many quantum emitters driving the laser mode. Here, small fluctuations in the laser lead to a broad background in the laser spectrum. Large fluctuations, occurring on exponentially long timescales, cause decoherence. In the second part of the dissertation, two possible applications of the HJL are investigated, both exploiting the phase lock. First, a well-known optical feedback technique is found to lead to significant stabilization of fluctuations in the bias voltage of the HJL, which cause drift of the optical and superconducting phases. After this, a HJL device is proposed based on the Superconducting Quantum Interference Device. In this `light-superconducting interference device’ (LSID), magnetic fields can be used to manipulate the laser light. The LSID is also shown to facilitate multimode lasing. Subject laserssuperconductorscoherence To reference this document use: https://doi.org/10.4233/uuid:32bbd6f5-151f-47c5-808e-815b48a119a6 Embargo date 2013-12-18 ISBN 9789085931713 Part of collection Institutional Repository Document type doctoral thesis Rights (c) 2014 Godschalk, F. Files PDF F-Godschalk-dissertation.pdf 5.06 MB Close viewer /islandora/object/uuid:32bbd6f5-151f-47c5-808e-815b48a119a6/datastream/OBJ/view