Dilute magnetic semiconductor quantum-well structures for magnetic field tunable far-infrared/terahertz absorption

Abstract

Article:Savic, I., Milanovic, V., Ikonic, Z. et Abstract-The design of ZnCdSe-ZnMnSe-based quantum wells is considered, in order to obtain a large shift of the peak absorption wavelength in the far infrared range, due to a giant Zeeman splitting with magnetic field, while maintaining a reasonably large value of peak absorption. A triple quantum-well structure with a suitable choice of parameters has been found to satisfy such requirements. A maximal tuning range between 14.6 and 34.7 meV is obtained, when the magnetic field varies from zero to 5 T, so the wavelength of the absorbed radiation decreases from 85.2 to 35.7 m with absorption up to 1.25% at low temperatures. These structures might form the basis for magnetic field tunable photodetectors and quantum cascade lasers in the terahertz range.Index Terms-Infrared detectors, manganese alloys, magnetic field effects, quantum wells, quantum theory, tunable circuits and devices.

Simulation of a tunable optically pumped terahertz intersubband laser with diluted magnetic semiconductors

“…The graded interface represents the diffusion region, taken to be 2 ML ͑monolayers͒ thick. Band offsets of Zn 1−x Mn x Se and Zn 1−y Cd y Se relative to ZnSe are, to a good approximation, linear functions of Mn and Cd concentrations 11 ⌬E cx = 520.7x meV,…”

“…[1][2][3][4][5][6] Several interband devices utilizing DMS were proposed, [7][8][9][10] but very few attempts were made in designing quantum intersubband devices based on DMS. 11 Application of external magnetic field leads to field-dependent splitting of the DMS conduction band edge. Variation of the magnetic field, material composition, or temperature changes the material parameters, which can be transformed into tunability of output characteristics via appropriate device design.…”

Lasing in spin‐polarized terahertz quantum cascade structures

“…Further development of the growth technology of dilute magnetic semiconductors (DMSs) [5] should enable implementation of similar intraband devices based upon them. The predictions of a large tunability of intraband transition energies and significant absorption/responsivity in THz DMS quantum wells (QWs)/quantum well infrared photodetectors [6,7] promote the idea of utilizing DMSs for tunable THz QCLs.In this paper, a design of a magnetically tunable THz QCL based on ZnMnSe/ZnMgSe is proposed, emitting in the region of 2.4 − 6.3 THz and 9.2 − 10.1 THz, corresponding to active laser levels transitions of 10 − 26 meV and 38 − 42 meV. Furthermore, the analysis of the possibility of achieving population inversion is presented, and the output characteristics of the designed QCL are calculated.…”

Magnetic-field tunable terahertz quantum well infrared photodetector

“…Some of the research activity has been oriented into the investigation of the spin splitting effects on interband transitions and the applications of DMSs in interband devices [9][10][11][12] . On the contrary, very few studies aiming towards novel intersubband devices based on DMSs have been reported 13 .…”

“…Magnetic field appears to offer great potential for tuning, if applied on structures based on DMSs. Due to the manipulation of the electronic structure by varying magnetic field, one can change the transition energies of the absorbed radiation 13 . Variations of a few meV which are achievable in CdMnTe (a DMS compound) imply a large tunability on a relative scale if the transition energy is in the THz range.…”