[PDF] Top 20 Measuring the sampling coherence of a terahertz quantum cascade laser

... each laser pulse, and L is the number of femtosecond pulses in the measurement, which is typically a very large ...the laser pulse is much less than the period of the THz wave, the laser pulses can ... See full document

... Terahertz quantum cascade lasers (THz QCLs) are compact, electrically driven sources of radia- tion in the ∼ 1–5 THz band [1] that hold enormous potential for sensing [2,3] and communication ... See full document

... FIG. 1. (a) Schematic of the experimental apparatus. Red lines are 80 fs NIR-pulses with a center wavelength of 800 nm, an 80 MHz repetition rate, and an approximately 1W of average power. Green lines are the THz beam ... See full document

... 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

... (THz) quantum cascade lasers (QCLs) [1] have stimulated significant interest in the development of imaging systems [2] at THz frequencies owing to their compact size, high output power (>1 W) [3] and ... See full document

... Terahertz quantum cascade lasers (THz QCLs) are compact, electrically driven sources of radia- tion in the ∼ 1–5 THz band [1] that hold enormous potential for sensing [2,3] and communication ... See full document

... The optical delay time was controlled using Newport ILS-200 motor translation stage, with a speed of 100 mm/s, and with measurements being triggered at 1- m increments over a maximum distance of 200 mm. The perturbation ... See full document

... In our technique, the depth resolution is determined by the sampling accuracy of the SM waveforms as well as the fre- quency instability of the laser caused by temperature and cur- rent fluctuations. The ... See full document

... One way to alleviate this problem is to use an array of external detectors to create a THz camera [1, 27]. Recent years have seen significant work on the development of THz cameras including the use of microbolometer ... See full document

... sample the same point in the envelope of the THz field. To achieve this integer link we use a fast photodiode, a tunable Yttrium Iron Garnet (YIG) bandpass filter and an amplifier chain to obtain the 170th harmonic of ... See full document

... The coherence coupling of the subbands in the neighboring period was described by Rabi oscillations, with energy ~ Ω , across the barrier separating the ...This coherence coupling is closely related with ... See full document

... a laser is partially reflected from an external target and injected back into the laser ...the laser SM signals are traditionally acquired from an external photodetector, we have recently ... See full document

... of terahertz (THz) frequency imaging sys- tems based on quantum cascade lasers ...gas laser line in order to reduce the phase instability of the emitted radiation field and allow the ... See full document

... A BTC QCL emitting at 2.6 THz was driven using a dc current source. The device used here has the same active region design and semi-insulating surface plasmon waveguide as the structure described in Ref. [15], although ... See full document

... (a) Measured graphene resistance (black line) and the output power of an external cavity laser (red line) for different back-gate voltage; (b) Transmission spectra of the SRR at four d[r] ... See full document

... The terahertz (THz) band is the part of electromagnetic spectrum located between photonics and electronics ...a quantum cascade laser (QCL) [9, ...diode laser which operates through the ... See full document

... Terahertz-frequency quantum cascade lasers (THz QCLs) are compact solid-state sources of coherent radiation in the 1–5 THz region of the electromagnetic spectrum [1], with output powers in excess of ... See full document

... V)-dependent laser parameters were determined using our full RE model in a grid of 13 tem- peratures and 38 electric field values, giving a total of 494 grid point values for each ... See full document

... the laser bars were cleaved to a cavity length of ...Ti:sapphire laser (200 ...Ti:sapphire laser synchronized to the QCL’s modulation using an acousto-optic ... See full document

... B.M.A Rahman (S’80-M’83-SM’94) received the B.Sc. Eng. and M.Sc. Eng. degrees (with distinctions) in electrical engineering from Bangladesh University of Engineering and Technology (BUET), Dhaka, Bangladesh, in 1976 and ... See full document