Integrated Terahertz Emitters and Detectors based on Quantum Optical Materials
Abstract
Integrated Terahertz Emitters and Detectors based on Quantum Optical MaterialsMona Jarrahi, University of California Los AngelesAppr,oved for Public ReleaseFurther revolutionary advances in the terahertz field requires a monolithically integrated terahertz optoelec,tronics platform to address the practical limitations posed by the large size, high cost, and complexity of existing terahertz syste,ms. The main roadblock against the development of monolithically-integrated terahertz systems has been the incompatibility of the op,tical sources, amplifiers, modulators, photoconductors, and control electronics used in these systems. On one hand, high-quality sem,iconductors are required for optical sources/amplifiers. On the other hand, short-carrier-lifetime semiconductors are required for u,ltrafast operation of photoconductors. Short-carrier-lifetime semiconductors are prepared by ion implantation, incorporating rare ea,rth compounds, and using low temperatures during the semiconductor growth. All of these techniques introduce a high density of carri,er trap sites within the semiconductor lattice and, therefore, cannot be used for optical generation/amplification. To address the i,ncompatibility problem of the building blocks of terahertz optoelectronic systems, we plan to investigate quantum well (QW) semicond,uctor structures as a novel backbone for terahertz optoelectronic systems. QW semiconductor structures have unique physical properti,es that enable monolithic integration of optical oscillators, amplifiers, waveguides, modulators, photoconductors, photodetectors, a,nd control electronics. On one hand, the energy of QW interband/intersubband transitions can be engineered, enabling stimulated/spon,taneous emission and amplification at the desired wavelengths. On the other hand, quantum-confined Stark shift of the QW semiconduct,or band structure can be controlled through the applied electric potential. Additionally, QW semiconductor structures are compatible, with metal-semiconductor field-effect transistor (MESFET) designs, enabling the realization of control electronic circuits side-by-,side the terahertz optoelectronic devices on the same, contact electrodes of photoconductors implemented along the QW waveguides can provide the ultrafast speeds required for terahertz s,ignal generation and detection, without any need for short-carrier-lifetime semiconductors. The main objective of the proposed resea,rch is realizing photoconductive terahertz emitters and detectors based on III-V QW structures that can be also used for generation,and amplification of optical pump beams with a terahertz beat frequency. Toward this objective, we plan to investigate photoconducti,at frequencies. During the proposed research, we plan to investigate the impact of the device geometry and the composition of the QW, structures on the performance of the photoconductive antennas realized through the III-V QW structures to be used as terahertz sour,ces and detectors. Specifically, we plan to study physical limitations for quantum efficiency, terahertz radiation power, and freque,ncy tunability for photoconductive terahertz sources realized through the III-V QW structures. We also plan to study physical limita,tions for responsivity, noise temperature, and frequency tunability for photoconductive terahertz detectors realized through the III,-V QW structures. The development of the proposed terahertz sources and detectors is a major milestone toward the realization of mon,olithically-integrated terahertz optoelectronics for future chip-scale terahertz imaging, sensing, and communication systems.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 13, 2022
- Source ID
- N000142212531
Entities
People
- Mona Jarrahi
Organizations
- Office of Naval Research
- United States Navy
- University of California, Los Angeles