Subscribe to the gold package and get unlimited access to Shamra Academy
Register a new userDemonstration of Si based InAs/GaSb type-II superlattice p-i-n photodetector
104
0
0.0
(
0
)
Ask ChatGPT about the research
No Arabic abstract
In this paper, mid-wave infrared photodetection based on an InAs/GaSb type-II superlattice p-i-n photodetector grown directly on Si substrate is demonstrated and characterized. Excitation power dependence on integrated intensity from the photoluminescence measurements reveals a power coefficient of P~I0.74, indicating that defects related process is playing an important role in the predominant recombination channel for photogenerated carriers. At 70 K, the device exhibits a dark current density of 2.3 A/cm2 under -0.1 V bias. Arrhenius analysis of dark current shows activation energies much less than half of the active layer bandgap, which suggests that the device is mainly limited by surface leakage and defect-assisted tunneling, consistent with the photoluminescence analysis. The detector shows 50% cutoff wavelength at ~5.5 um at 70 K under bias of -0.1 V. The corresponding peak responsivity and specific detectivity are 1.2 A/W and 1.3*10e9 cm*Hz1/2/W, respectively. Based on these optoelectronics characterization results, reduction of defects by optimizing the III/V-Si interface, and suppression of surface leakage channels are argued to be the main factors for performance improvement in this Si-based T2SL detector towards low cost, large-format MWIR detection system on Si photonics platform.
rate research
Read More
The cross-plane thermal conductivity of a type II InAs/GaSb superlattice (T2SL) is measured from 13 K to 300 K using the 3{omega} method. Thermal conductivity is reduced by up to 2 orders of magnitude relative to the GaSb bulk substrate. The low thermal conductivity of around 1-8 W/mcdotK may serve as an advantage for thermoelectric applications at low temperatures, while presenting a challenge for T2SL quantum cascade lasers and high power light emitting diodes. We introduce a power-law approximation to model non-linearities in the thermal conductivity, resulting in increased or decreased peak temperature for negative or positive exponents, respectively.
High speed mid-wave infrared (MWIR) photodetectors have important applications in the emerging areas such high-precision frequency comb spectroscopy and light detection and ranging (LIDAR). In this work, we report a high-speed room-temperature mid-wave infrared interband cascade photodetector (ICIP) based on a type-II InAs/GaSb superlattice. The devices show an optical cut-off wavelength around 5um and a 3-dB bandwidth up to 7.04 GHz. The relatively low dark current density around 9.39 x 10-2 A/cm2 under -0.1 V is also demonstrated at 300 K. These results validate the advantages of ICIPs to achieve both high-frequency operation and low noise at room temperature. Limitations on the high-speed performance of the detector are also discussed based on the S-parameter analysis and other RF performance measurement.
We present transport measurements on a lateral p-n junction in an inverted InAs/GaSb double quantum well at zero and nonzero perpendicular magnetic fields. At a zero magnetic field, the junction exhibits diodelike behavior in accordance with the presence of a hybridization gap. With an increasing magnetic field, we explore the quantum Hall regime where spin-polarized edge states with the same chirality are either reflected or transmitted at the junction, whereas those of opposite chirality undergo a mixing process, leading to full equilibration along the width of the junction independent of spin. These results lay the foundations for using p-n junctions in InAs/GaSb double quantum wells to probe the transition between the topological quantum spin Hall and quantum Hall states.
In this work, we report a polarized Raman study on the vibrational properties of the InAs/InAs1-xSbx SLs as well as selected InAs1-xSbx alloys, all grown on GaSb substrates by either MBE or MOCVD, from both growth surface and cleaved edge.
The detection of light helicity is key to several research and industrial applications from drugs production to optical communications. However, the direct measurement of the light helicity is inherently impossible with conventional photodetectors based on III-V or IV-VI semiconductors, being naturally non-chiral. The prior polarization analysis of the light by a series of often moving optical elements is necessary before light is sent to the detector. A method is here presented to effectively give to the conventional dilute nitride GaAs-based semiconductor epilayer a chiral photoconductivity in paramagnetic-defect-engineered samples. The detection scheme relies on the giant spin-dependent recombination of conduction electrons and the accompanying spin polarization of the engineered defects to control the conduction band population via the electrons spin polarization. As the conduction electron spin polarization is, in turn, intimately linked to the excitation light polarization, the light polarization state can be determined by a simple conductivity measurement. This effectively gives the GaAsN epilayer a chiral photoconductivity capable of discriminating the handedness of an incident excitation light in addition to its intensity. This approach, removing the need of any optical elements in front of a non-chiral detector, could offer easier integration and miniaturisation. This new chiral photodetector could potentially operate in a spectral range from the visible to the infra-red using (In)(Al)GaAsN alloys or ion-implanted nitrogen-free III-V compounds.
Log in to be able to interact and post comments
comments
Fetching comments
Sign in to be able to follow your search criteria
