Prof. Huiyun Liu Profile

Prof. Huiyun Liu

Professor at Univ College London

SPIE Involvement:

Conference Program Committee | Author

Publications (27)

PROCEEDINGS ARTICLE | May 23, 2018

Continuous wavelength operation of injection III-V microdisk lasers directly grown on Si substrate with emission wavelength beyond 1.2 µm (Conference Presentation)

Proc. SPIE. 10682, Semiconductor Lasers and Laser Dynamics VIII

KEYWORDS: Quantum wells, Optical lithography, Resonators, Silicon, Quantum dots, Semiconductor lasers, Plasma etching, Photonic integrated circuits, Laser damage threshold, Plasma

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A combination of high operation temperatures and small sizes of diode lasers directly grown on silicon substrates is essential for their application in future photonic integrated circuits. In this work, we report on electrically-pumped III-V microdisk lasers monolithically grown on Si substrates with active regions of two kinds: either an InGaAs/GaAs quantum well (QW) or InAs/InGaAs/GaAs quantum dots (QDs). Microdisk resonators were defined using photolithography and plasma chemical etching. The active region diameter was varied from 11 to 31 µm. Microlasers were tested without external cooling at room and elevated temperatures. The QW laser structure was epitaxially grown by MOCVD on silicon (100) with an intermediate MBE-grown Ge buffer. Under pulsed injection (0.5-µs-long injection pulses with 150 Hz repetition rate), lasing is achieved in QW microlasers with diameters of 23-31 µm with a minimal threshold current density of 28 kA/cm^2. Quasi-single mode lasing (SMSR is up to 20 dB) is observed with emission wavelength around 988 nm. To the best of our knowledge, this is the first quantum well electrically-pumped microdisk lasers monolithically deposited on (001)-oriented Si substrate. Quantum wells are typically characterized by high optical gain and high direct modulation bandwidth, which can be important in view of further miniaturization of microlasers and their future application. The sidewall passivation can be helpful to reduce the threshold current. As compared to QWs, quantum dots demonstrate reduced sensitivity to threading dislocations and other crystalline defects as well as to sidewall recombination owing to a suppressed lateral transport of charge carriers which prevents their diffusion towards non-radiate recombination centers. The QD laser structure was directly grown by MBE on Si (001) substrate with 4° offcut to the [011] plane. QD microlasers were tested at room temperature in CW regime with a DC current varied from 0 to 50 mA and at elevated temperatures under CW and pulsed excitation (0.5-µs-long injection pulses with 10 kHz repetition rate). The InAs/InGaAs QDs active region provides the wavelengths in the 1.32–1.35 µm spectral interval. At room temperature, lasing is achieved in microlasers with diameters of 14-30 µm with a minimal threshold current density of 600 A/cm2 (compare with that of 427 A/cm2 in edge-emitting laser). The threshold current density and specific thermal resistance of 0.004 °C×cm^2/mW are comparable to those of high-quality QD microdisk lasers on GaAs substrates. Lasing wavelength demonstrates low sensitivity to current-induced self-heating. Lasing is single mode (SMSR 20 dB) with a dominant mode linewidth as narrow as 30 pm. Under CW excitation lasing sustains up to 60 °C in microlasers with diameter of 30 µm. Because of self-heating, an actual temperature of the active region is close to 100°C. Under pulsed excitation, the maximal lasing temperature is 110°C. To our best knowledge, these are the smallest microlasers on silicon operating at such elevated temperatures ever reported. Up to 90°C lasing proceeds on the ground state optical transition of QDs with wavelength about 1.35 µm. At higher temperatures, lasing wavelength jumps to the excited state transition.

PROCEEDINGS ARTICLE | March 14, 2018

High-responsivity photodetection using a single p-type GaAs nanowire (Conference Presentation)

Proc. SPIE. 10543, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XV

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PROCEEDINGS ARTICLE | January 26, 2018

Resonant scattering probes for terahertz near-field microscopy

Proc. SPIE. 10540, Quantum Sensing and Nano Electronics and Photonics XV

KEYWORDS: Indium arsenide, Scattering, Microscopy, Near field scanning optical microscopy, Near field, Terahertz radiation, Antennas

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PROCEEDINGS ARTICLE | February 23, 2017

Influence of Si doping on InAs/GaAs quantum dot solar cells with AlAs cap layers

Proc. SPIE. 10099, Physics, Simulation, and Photonic Engineering of Photovoltaic Devices VI

KEYWORDS: Indium arsenide, External quantum efficiency, Solar cells, Gallium arsenide, Silicon, Doping, Quantum dots, Chlorine, Gallium, Molecular beam epitaxy, Absorption

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PROCEEDINGS ARTICLE | February 20, 2017

Influence of droplet size on the growth of high-quality self-catalyzed GaAsP nanowires

Proc. SPIE. 10114, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIV

KEYWORDS: Thin films, Crystals, Gallium arsenide, Silicon, Photonic crystals, Scanning electron microscopy, Gallium, Photonic crystal devices, Arsenic, Nanowires

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PROCEEDINGS ARTICLE | February 20, 2017

Integrating III-V quantum dot lasers on silicon substrates for silicon photonics

Proc. SPIE. 10108, Silicon Photonics XII

KEYWORDS: Optical filters, Electronics, Continuous wave operation, Gallium arsenide, Indium, Semiconductor materials, Silicon, Quantum dots, Semiconductor lasers, Photonics, Laser damage threshold, Silicon photonics, Gallium, Molecular beam epitaxy, Quantum dot lasers, Light

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PROCEEDINGS ARTICLE | January 27, 2017

GaAsP nanowires and nanowire devices grown on silicon substrates

Proc. SPIE. 10111, Quantum Sensing and Nano Electronics and Photonics XIV

KEYWORDS: Photovoltaics, Solar cells, Crystals, Gallium arsenide, Silicon, Transmission electron microscopy, Gallium, Arsenic, Water splitting, Nanowires

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PROCEEDINGS ARTICLE | March 15, 2016

Analysing radiative and non-radiative recombination in InAs QDs on Si for integrated laser applications

Proc. SPIE. 9758, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIII

KEYWORDS: Indium arsenide, Annealing, Luminescence, Interfaces, Gallium arsenide, Silicon, Laser applications, Data transmission, Quantum dots, Semiconductor lasers, Electronic components, Integrated optics, Laser damage threshold, Silicon photonics, Instrument modeling

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PROCEEDINGS ARTICLE | March 15, 2016

Growth of high-quality self-catalyzed core-shell GaAsP nanowires on Si substrates

Proc. SPIE. 9758, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIII

KEYWORDS: Photovoltaics, Visible radiation, Solar cells, Luminescence, Crystals, Silicon, Zinc, Scanning electron microscopy, Transmission electron microscopy, Structural design, Chemical elements, Gallium, Arsenic, Molecular beam epitaxy, Thin film growth, Water splitting, Nanowires

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PROCEEDINGS ARTICLE | March 15, 2016

InAs/GaAs quantum-dot light emitters monolithically grown on Si substrate

Proc. SPIE. 9758, Quantum Dots and Nanostructures: Growth, Characterization, and Modeling XIII

KEYWORDS: Fabrication, Metamaterials, Plasmonics, Light emitting diodes, Indium arsenide, Copper, Gallium arsenide, Silicon, Atomic force microscopy, Quantum dots, Semiconductor lasers, Transmission electron microscopy, Laser damage threshold, Silicon photonics, Pulsed laser operation, Molecular beam epitaxy, Hybrid silicon lasers

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PROCEEDINGS ARTICLE | March 14, 2016

1.7eV Al0.2Ga0.8As solar cells epitaxially grown on silicon by SSMBE using a superlattice and dislocation filters

Proc. SPIE. 9743, Physics, Simulation, and Photonic Engineering of Photovoltaic Devices V

KEYWORDS: Photovoltaics, External quantum efficiency, Calibration, Solar cells, Gallium arsenide, Silicon, Transmission electron microscopy, Superlattices, Molecular beam epitaxy, Group III-V semiconductors, Laser sintering

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PROCEEDINGS ARTICLE | March 14, 2016

Simulation study of GaAsP/Si tandem cells including the impact of threading dislocations on the luminescent coupling between the cells

Proc. SPIE. 9743, Physics, Simulation, and Photonic Engineering of Photovoltaic Devices V

KEYWORDS: Photovoltaics, Solar energy, Solar cells, Luminescence, Photons, Silicon, Diffusion, Silicon solar cells, Computer architecture, Performance modeling, Group III-V semiconductors, Tandem solar cells, Absorption

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PROCEEDINGS ARTICLE | May 21, 2015

Design and fabrication of indium phosphide air-bridge waveguides with MEMS functionality

Proc. SPIE. 9517, Smart Sensors, Actuators, and MEMS VII; and Cyber Physical Systems

KEYWORDS: Microelectromechanical systems, Electron beam lithography, Refractive index, Indium gallium arsenide, Waveguides, Etching, Indium, Geometrical optics, Indium gallium phosphide, Light wave propagation

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PROCEEDINGS ARTICLE | February 27, 2015

Optimising the defect filter layer design for III/V QDs on Si for integrated laser applications

Proc. SPIE. 9373, Quantum Dots and Nanostructures: Synthesis, Characterization, and Modeling XII

KEYWORDS: Optical filters, Annealing, Luminescence, Gallium arsenide, Silicon, Laser applications, Semiconductor lasers, Transmission electron microscopy, Excitons, Superlattices

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PROCEEDINGS ARTICLE | February 27, 2015

Optical characterisation of catalyst free GaAsP and GaAsP core-shell nanowires grown directly on Si substrates by MBE

Proc. SPIE. 9373, Quantum Dots and Nanostructures: Synthesis, Characterization, and Modeling XII

KEYWORDS: Luminescence, Crystals, Gallium arsenide, Silicon, Zinc, Scanning electron microscopy, Solids, Gallium, Molecular beam epitaxy, Nanowires

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PROCEEDINGS ARTICLE | February 27, 2015

Tunable optical buffer based on III-V MEMS design

Proc. SPIE. 9375, MOEMS and Miniaturized Systems XIV

KEYWORDS: Microelectromechanical systems, Electron beam lithography, Optical design, Indium gallium arsenide, Waveguides, Etching, Electrodes, Wave propagation, Group III-V semiconductors, Indium gallium phosphide

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PROCEEDINGS ARTICLE | January 29, 2008

High-performance 1300-nm InAs/GaAs quantum-dot lasers

Proc. SPIE. 6909, Novel In-Plane Semiconductor Lasers VII

KEYWORDS: Indium gallium arsenide, Continuous wave operation, Indium arsenide, Modulation, Gallium arsenide, Doping, Scanning probe lithography, Quantum dots, Laser damage threshold, Temperature metrology

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PROCEEDINGS ARTICLE | January 11, 2008

Effects of spacer growth temperature on the optical properties of quantum dot laser structures

Proc. SPIE. 6800, Device and Process Technologies for Microelectronics, MEMS, Photonics, and Nanotechnology IV

KEYWORDS: Quantum wells, Indium arsenide, Optical properties, Gallium arsenide, Electroluminescence, Quantum dots, Transmission electron microscopy, Gallium, Quantum dot lasers, Temperature metrology

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PROCEEDINGS ARTICLE | March 22, 2007

Maximising the gain: optimizing the carrier distribution in InGaAs quantum dot lasers

Proc. SPIE. 6468, Physics and Simulation of Optoelectronic Devices XV

KEYWORDS: Indium gallium arsenide, Transparency, Gallium arsenide, Doping, Quantum dots, Laser damage threshold, Semiconducting wafers, Quantum dot lasers, Temperature metrology, Absorption

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PROCEEDINGS ARTICLE | October 3, 2006

High power and very low noise operation at 1.3 and 1.5 um with quantum dot and quantum dash Fabry-Perot lasers for microwave links

Proc. SPIE. 6399, Advanced Free-Space Optical Communication Techniques/Applications II and Photonic Components/Architectures for Microwave Systems and Displays

KEYWORDS: Fabry–Perot interferometers, Quantum wells, Waveguides, High power lasers, Gallium arsenide, Laser applications, Quantum dots, Laser damage threshold, Microwave radiation, Quantum dot lasers

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PROCEEDINGS ARTICLE | April 14, 2006

Dilute nitride-based 1.3μm high performance lasers

Proc. SPIE. 6184, Semiconductor Lasers and Laser Dynamics II

KEYWORDS: Quantum wells, Transparency, Optical properties, Luminescence, Gallium arsenide, Indium, Nitrogen, Laser damage threshold, Temperature metrology, Plasma

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PROCEEDINGS ARTICLE | April 14, 2006

High performance 1.3μm InAs/GaAs quantum dot lasers with low threshold current and negative characteristic temperature

Proc. SPIE. 6184, Semiconductor Lasers and Laser Dynamics II

KEYWORDS: Continuous wave operation, Indium arsenide, Modulation, Gallium arsenide, Coating, Doping, Scanning probe lithography, Quantum dots, Laser damage threshold

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PROCEEDINGS ARTICLE | February 22, 2006

Characterisation of modulation doped quantum dot lasers

Proc. SPIE. 6133, Novel In-Plane Semiconductor Lasers V

KEYWORDS: Quantum wells, Transparency, Modulation, Gallium arsenide, Doping, Quantum dots, Semiconductor lasers, Laser damage threshold, Gallium, Absorption

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PROCEEDINGS ARTICLE | February 7, 2006

Broad-band superluminescent light emitting diodes incorporating quantum dots in compositionally modulated quantum wells

Proc. SPIE. 6129, Quantum Dots, Particles, and Nanoclusters III

KEYWORDS: Quantum wells, Light emitting diodes, Indium arsenide, Modulation, Optical coherence tomography, Gallium arsenide, Indium, Quantum dots, Gallium

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PROCEEDINGS ARTICLE | July 7, 2005

Influence of structure and defects on the performance of dot-in-well laser structures

Proc. SPIE. 5840, Photonic Materials, Devices, and Applications

KEYWORDS: Indium gallium arsenide, Quantum wells, Indium arsenide, Gallium arsenide, Indium, Atomic force microscopy, Quantum dots, Transmission electron microscopy, Photomicroscopy, Gallium

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PROCEEDINGS ARTICLE | April 13, 2005

Time-resolved photoluminescence measurements of InAs self-assembled quantum dots

Proc. SPIE. 5725, Ultrafast Phenomena in Semiconductors and Nanostructure Materials IX

KEYWORDS: Indium arsenide, Sensors, Luminescence, Gallium arsenide, Quantum dots, Time metrology, Aluminum, Picosecond phenomena, Gallium, Temperature metrology

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PROCEEDINGS ARTICLE | April 1, 2005

Growth and characterization of multiple layer quantum dot lasers

Proc. SPIE. 5738, Novel In-Plane Semiconductor Lasers IV

KEYWORDS: Multilayers, Quantum wells, Gallium arsenide, Quantum dots, Semiconductor lasers, Transmission electron microscopy, Laser damage threshold, Gallium, Quantum dot lasers, Absorption

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