[PDF] Top 20 Infinite-period density-matrix model for terahertz-frequency quantum cascade lasers

... Various models for transport in QCLs exist [12]: most commonly employing semiclassical approaches such as self- consistent rate-equation (RE) modeling, which considers non- radiative transitions of carriers due to the ... See full document

... developed terahertz frequency quantum cascade lasers that exploit a double-periodicity distributed feedback grating to control the emission frequency and the output beam ... See full document

... analytical model based on the assumption that an IMPATT diode is formed at the injection ...The model is based on the calculation of the static elec- tric field distribution in the contact region, and the ... See full document

... a terahertz (THz) frequency quantum cascade laser (QCL) using an extended density matrix (DM) ...DM model allows calculation of both the current–voltage (I–V ) and optical ... See full document

... ប ␻ ⬇ E ¯ 1 ⬘ − E ¯ 2 , respectively兲, there is no additional contribu- tion of resonant LO phonon-assisted optical transitions for the QCL considered. In contrast, for photon energies close to one LO phonon energy, such ... See full document

... transport model the applied field and cavity loss are inputs to the model, while current is a calculated ...current density were calculated between fields of ... See full document

... emission frequency over bandwidths of 50 GHz and 80 GHz, respectively, as the shorter section of the device was electrically ...Vernier frequency tuning far exceeds the tuning achievable from standard ridge ... See full document

... extended density matrix (DM) approach was used to simulate the carrier transport ...one period were calculated based on a tight-binding model, in which a period of the QCL structure is ... See full document

... in the waveguide cladding thickness, which is particularly advantageous for terahertz (THz) frequency QCLs since the growth of suitably thick dielectric waveguides is impractical. Indeed, the first THz QCL ... See full document

... The applicability of this DRI scheme to the spatial map- ping of powdered materials was initially demonstrated using exemplar powdered admixtures of polymethyl methacrylate (PMMA) and polystyrene. PMMA exhibits strong ... See full document

... Light-current-voltage and far-field characterization. Devices with two different groove widths were fabricated, labeled as A and B. The groove widths of device A were 600 mm, whilst device B had a wider groove width of ... See full document

... (315 GHz, 155 GHz, 115 GHz, and 80 GHz for cavity lengths of 125 lm, 255 lm, 350 lm, and 515 lm, respectively). In an effective mirror picture, this is produced by the etalon effect of the short cavity þ air gap, which ... See full document

... at terahertz frequencies: Towards imaging and identification of plastic explosives,” Sensors 16(3), 352 ...“Biomedical terahertz imaging with a quantum cascade laser,” ... See full document

... other) model of V (t) expressed in terms of I(t) and T ...to model theoretically, than those of diode ...behavioral model based on measured temperature-dependent IV data, rather than use ... See full document

... this frequency range, such as its non-ionising nature and its extreme sensitivity to tissue water content, THz imaging holds great promises for diagnostics and non-destructive analysis of biological ...a ... See full document

... Figure 3 shows the LI curve of a CCG DFB QCL com- pared with that of a ridge-waveguide laser of similar area. An increased output power, by a factor of approximately three times, is measured. Owing to the Stark effect of ... See full document

... in frequency space, thought to be due to increased frequency filtering of the MM waveguide which has much higher loss for frequencies outside the ... See full document

... or quantum, a dimensionless parameter ̅ has been introduced ...the quantum regime ...the quantum regime, an electron can be represented as a two level system, and each electron emits at most one ... See full document

... Laser feedback interferometry, also known as SM interferometry, is a coherent sensing scheme that employs a laser as a homodyne transceiver. Laser feedback interferometry relies on the remarkably universal SM effect — ... See full document

... The transmission images of the 26 vol % PETN pellet acquired at each frequency are shown in figure 7. The image size is 44  44 pixels, corresponding to an area measuring 11 mm  11 mm, and the images have been ... See full document