Quantum Device Laboratory (QDL) at OU is working on quantum engineered semiconductor structures in sub-nanometer scale for realizing functional devices and sub-systems with support from NSF, DoD, and DoE.
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Prof. Rui Q. Yang and PhD Student Yixuan Shen Present at CLEO 2024
Figure 1: Prof. Rui Q. Yang presenting his invited talk on mid-infrared interband cascade devices.
Figure 2: Yixuan Shen presenting his research on long-wavelength interband cascade lasers.
Charlotte, NC, May 2024 – Prof. Rui Q. Yang and PhD student Yixuan Shen recently attended the Conference on Lasers and Electro-Optics (CLEO) 2024, in Charlotte, North Carolina, USA.
Prof. Yang delivered an invited talk titled “Mid-infrared Interband Cascade Devices for Sensing Applications,” showcasing the latest advancements in mid-infrared interband cascade lasers, interband cascade infrared photodetector and their potential for various sensing applications (see Figure 1).
PhD student Yixuan Shen also made a contribution to the conference by presenting his research on “Long Wavelength Interband Cascade Lasers using Innovative Quantum Well Active Regions.” His presentation highlighted the use of innovative quantum well structures to achieve long-wavelength emission in interband cascade lasers (see Figure 2).
The CLEO conference is renowned for its comprehensive technical program that covers all aspects of laser science and photonics applications. The participation of Prof. Yang and Yixuan underscores our group’s mission to advancing the field of laser technology and fostering a collaborative research environment.
Recent publications
Continuous wave interband cascade lasers near 13 μm
Yixuan Shen, Rui Q. Yang, Samuel D. Hawkins, Aaron J. Muhowski
We report the demonstration of continuous-wave interband cascade lasers (ICLs) near 13 μm. The attained lasing wavelength of 13.2 μm at 92 K stands as the longest cw emission wavelength ever reported for III-V interband lasers. This achievement is attributed to the adoption of an innovative quantum well (QW) active region comprising strained InAs0.5P0.5 layers in contrast to the commonly used “W” QW active region, showing the potential of the modified QW active region with InAsP layers in improving device performance and extending wave- length coverage of ICLs.
Shot and Johnson noises in interband cascade infrared photodetectors
Rui Q. Yang, “Shot and Johnson noises in interband cascade infrared photodetectors”, Appl. Phys. Lett. 121, 51105 (2022)
Shot and Johnson noises are often incorrectly thought of as two independent noise sources. This incorrect picture has affected the evaluation of detectivities in interband cascade infrared photodetectors (ICIPs). In this work, a unified picture of shot and Johnson noises is developed for ICIPs based on a fundamental framework to understand the origin of Johnson noise and clarify the possible confusion between Johnson and shot noises. General, yet concise expressions are derived to evaluate the current noise power spectral density and detectivity for ICIPs even with complicated structures. Also, simple expressions for the signal current due to absorption of photons and the corresponding photon noise are derived, consistent with the previous results derived from alternative methods. Furthermore, a formula is derived to correctly evaluate the detectivity for conventional photodetectors under a reverse bias. The derived formulas with discussion are expected to improve the understanding of noises in ICIPs and other types of photodetectors and help us to appropriately evaluate their detectivities.
Single-mode interband cascade laser based on V-coupled cavity with 210 nm wavelength tuning range near 3 μm
Jingli Gong, Zhanyi Wang, Jian-Jun He, Lu Li, Rui Q. Yang, and James A. Gupta
By enhancing the coupling coefficient and using a type-I ICL wafer, single-mode ICLs were demonstrated based on V-coupled cavity with significantly extended tuning range and with a side mode suppression ratio (SMSR) exceeding 35 dB in continuous wave operation near 3 μm. A V-coupled cavity ICL exhibited a wavelength tuning up to 67 nm at a fixed temperature, and the total tuning range exceeds 210 nm when the heat sink temperature is adjusted from 80 to 180 K. The realization of single-mode in such a wide temperature range with a tuning range exceeding 210 nm verified the advantage of V-coupled cavity ICLs for effective detection of multiple gas species. Another V-coupled cavity ICL is tuned over 120 nm from 2997.56 nm to 3117.50 nm with the heat-sink temperature varied from 210 K to 240 K, over 100 K higher than the previously reported maximum operating temperature for V-coupled cavity ICLs.
Improved Device Performance of Interband Cascade Lasers with Hybrid Cladding Layers Operating in the 3-4 μm wavelength region
Yixuan Shen, Jeremy A. Massengale, Rui Q. Yang, Tetsuya D. Mishima, Michael B. Santos
By focusing on a hybrid cladding approach, we demonstrate substantially improved device performance of ICLs compared to earlier reported ICLs of a similar design in the 3–4 µm wavelength region. Including a Jth for broad-area devices as low as 134 A/cm2 at 300 K and a peak voltage efficiency of 80%. Moreover, we have demonstrated CW operation of a BA device up to 278 K, the highest CW operating temperature among epi-side up mounted broad-area type-II ICLs, implying improved thermal dissipation with the hybrid cladding approach.
