High performance InAs quantum dot lasers on silicon substrates by low temperature Pd-GaAs wafer bonding [PDF]

Zihao Wang, Ruizhe Yao, Stefan F. Preble, Chi-Sen Lee, Luke F. Lester, and Wei Guo
Applied Physics Letters 107, 261107 (2015)

InAs quantum dot (QD) laser heterostructures have been grown by molecular beam epitaxy on GaAs substrates, and then transferred to silicon substrates by a low temperature (250C) Pd-mediated wafer bonding process. A low interfacial resistivity of only 0.2Ohm-cm^2 formed during the bonding process is characterized by the current-voltage measurements. The InAs QD lasers on Si exhibit comparable characteristics to state-of-the-art QD lasers on silicon substrates, where the threshold current density Jth and differential quantum efficiency of 240 A/cm2 and 23.9%, respectively, at room temperature are obtained with laser bars of cavity length and waveguide ridge of 1.5mm and 5um, respectively. The InAs QD lasers also show operation up to 100C with a threshold current density Jth and differential quantum efficiency of 950 A/cm2 and 9.3%, respectively. The temperature coefficient T0 of 69K from 60 to 100C is characterized from the temperature dependent Jth measurements.
On-Chip Quantum Interference from a Single Silicon Ring-Resonator Source [PDF]

Stefan F. Preble, Michael L. Fanto, Jeffrey A. Steidle, Christopher C. Tison, Gregory A. Howland, Zihao Wang, and Paul M. Alsing
Phys. Rev. Applied 4, 021001 (2015)

Silicon photonics is a promising platform to realize the dense and scalable integration required for quantum computing, communication, and sensing. The authors demonstrate a key building block for this platform, a simple, single source of entangled photons, and use it to observe quantum interference on the same chip. This removes the need for clumsy interfacing of multiple photon sources, as in previous studies, and provides a basis for highly scalable photonic circuits that achieve multi-qubit entanglement.
Hybrid amorphous silicon(a-Si:H)–LiNbO3 electro-optic modulator [PDF]

Liang Cao, Abdelsalam Aboketaf, Zihao Wang, Stefan Preble
Optics Communications 330, 40–44 (2014)

Here we report the demonstration of a GHz-speed Lithium Niobate (LiNbO3) modulator that uses an amorphous Silicon waveguide to strongly confine light. The compact (<1mm) modulator is realized by low-temperature deposition of hydrogenated amorphous Silicon (a-Si:H) onto a x-cut LiNbO3 substrate. The a-Si:H provides tight waveguide mode confinement while allowing strong evanescent coupling to the underlying LiNbO3 substrate which, in turn, enables efficient electro-optic modulation. This approach overcomes the traditional drawbacks of low-index contrast LiNbO3 waveguides and consequently is able to realize a strong Pockels effect in a densely integrated Silicon photonics platform. It is expected that this new Si-LiNbO3 platform will enable a multitude of devices and circuits for RF Photonics, nonlinear optics and quantum optics.

Scalable Hong-Ou-Mandel manifolds in quantum-optical ring resonators [PDF]

Edwin E. Hach, III, Stefan F. Preble, Ali W. Elshaari, Paul M. Alsing, Michael L. Fanto
Physical Review A 89, 043805 (2014)

Quantum information processing, from cryptography to computation, based upon linear quantum-optical circuit elements relies heavily on the ability offered by the Hong-Ou-Mandel (HOM) effect to “route” photons from separate input modes into one of two common output modes. Specifically, the HOM effect accomplishes the path entanglement of two photons at a time such that no coincidences are observed in the output modes of a system exhibiting the effect. In this paper, we prove, in principle, that by operating a specific nanophotonic device properly, one can conditionally “bunch” coincident input photons in a way that is more configurable than with an ordinary 50:50 beam splitter, while maintaining the inherent scalability of such an on-chip device.

Cao, Liang, Abdelsalam Aboketaf, Zihao Wang, and Stefan Preble. “Hybrid Amorphous Silicon (a-Si:H)–LiNbO3 Electro-optic Modulator.” Optics Communications 330 (November 2014): 40–44. doi:10.1016/j.optcom.2014.05.021. (Download)
Hach, Edwin E., III, Stefan F. Preble, Ali W. Elshaari, Paul M. Alsing, and Michael L. Fanto. “Scalable Hong-Ou-Mandel Manifolds in Quantum-optical Ring Resonators.” Physical Review A 89, no. 4 (April 3, 2014): 043805. doi:10.1103/PhysRevA.89.043805.
Bhattacharya, M., H. Shi, and S. Preble. “Coupled Second-quantized Oscillators.” American Journal of Physics 81, no. 4 (March 18, 2013): 267–273. doi:10.1119/1.4792696.
Cao, Liang, Abdelsalam A. Aboketaf, and Stefan F. Preble. “CMOS Compatible Micro-oven Heater for Efficient Thermal Control of Silicon Photonic Devices.” Optics Communications 305 (September 15, 2013): 66–70. doi:10.1016/j.optcom.2013.05.003.
Mee, J. K., M. T. Crowley, N. Patel, D. Murrell, R. Raghunathan, A. Aboketaf, A. Elshaari, S. F. Preble, P. Ampadu, and L. F. Lester. “A Passively Mode-locked Quantum-dot Laser Operating over a Broad Temperature Range.” Applied Physics Letters 101, no. 7 (August 14, 2012): 071112. doi:10.1063/1.4746266.
Adams, Donald, Abdelsalam Aboketaf, and Stefan Preble. “Robust Phase-shift-keying Silicon Photonic Modulator.” Optics Express 20, no. 16 (July 17, 2012): 17440. doi:10.1364/OE.20.017440. (Download)
Preble, Stefan, Liang Cao, Ali Elshaari, Abdelsalam Aboketaf, and Donald Adams. “Single Photon Adiabatic Wavelength Conversion.” Applied Physics Letters 101, no. 17 (October 24, 2012): 171110. doi:10.1063/1.4764068. (Download)
Elshaari, Ali W., and Stefan F. Preble. “10 Gb/s Broadband Silicon Electro-optic Absorption Modulator.” Optics Communications 283, no. 14 (July 15, 2010): 2829–2834. doi:10.1016/j.optcom.2010.03.048.
Narayanan, Karthik, and Stefan F. Preble. “Generation of Amplitude-shift-keying Optical Signals Using Silicon Microring Resonators.” Optics Express 18, no. 5 (February 25, 2010): 5015. doi:10.1364/OE.18.005015.
Aboketaf, Abdelsalam A., Ali W. Elshaari, and Stefan F. Preble. “Optical Time Division Multiplexer on Silicon Chip.” Optics Express 18, no. 13 (June 8, 2010): 13529. doi:10.1364/OE.18.013529.
Elshaari, Ali W., Abdelsalam Aboketaf, and Stefan F. Preble. “Controlled Storage of Light in Silicon Cavities.” Optics Express 18, no. 3 (January 28, 2010): 3014. doi:10.1364/OE.18.003014.
Narayanan, Karthik, Ali W. Elshaari, and Stefan F. Preble. “Broadband All-optical Modulation in Hydrogenated-amorphous Silicon Waveguides.” Optics Express 18, no. 10 (April 27, 2010): 9809. doi:10.1364/OE.18.009809.
Narayanan, Karthik, and Stefan F. Preble. “Optical Nonlinearities in Hydrogenated-amorphous Silicon Waveguides.” Optics Express 18, no. 9 (April 14, 2010): 8998. doi:10.1364/OE.18.008998.
Hach, Edwin E., Ali W. Elshaari, and Stefan F. Preble. “Fully Quantum-mechanical Dynamic Analysis of Single-photon Transport in a Single-mode Waveguide Coupled to a Traveling-wave Resonator.” Physical Review A 82, no. 6 (December 30, 2010): 063839. doi:10.1103/PhysRevA.82.063839.
Dong, Po, Stefan F. Preble, Jacob T. Robinson, Sasikanth Manipatruni, and Michal Lipson. “Inducing Photonic Transitions Between Discrete Modes in a Silicon Optical Microcavity.” Physical Review Letters 100, no. 3 (January 25, 2008): 033904. doi:10.1103/PhysRevLett.100.033904.
Dong, Po, Stefan F. Preble, and Michal Lipson. “All-optical Compact Silicon Comb Switch.” Optics Express 15, no. 15 (2007): 9600. doi:10.1364/OE.15.009600.
Preble, Stefan F., Qianfan Xu, and Michal Lipson. “Changing the Colour of Light in a Silicon Resonator.” Nature Photonics 1, no. 5 (May 2007): 293–296. doi:10.1038/nphoton.2007.72. (Download)
Gondarenko, Alexander, Stefan Preble, Jacob Robinson, Long Chen, Hod Lipson, and Michal Lipson. “Spontaneous Emergence of Periodic Patterns in a Biologically Inspired Simulation of Photonic Structures.” Physical Review Letters 96, no. 14 (April 13, 2006): 143904. doi:10.1103/PhysRevLett.96.143904.
Robinson, Jacob T., Stefan F. Preble, and Michal Lipson. “Imaging Highly Confined Modes in Sub-micron Scale Silicon Waveguides Using Transmission-based Near-field Scanning Optical Microscopy.” Optics Express 14, no. 22 (2006): 10588. doi:10.1364/OE.14.010588.
Preble, Stefan, Michal Lipson, and Hod Lipson. “Two-dimensional Photonic Crystals Designed by Evolutionary Algorithms.” Applied Physics Letters 86, no. 6 (February 3, 2005): 061111. doi:10.1063/1.1862783.
Preble, Stefan F., Qianfan Xu, Bradley S. Schmidt, and Michal Lipson. “Ultrafast All-optical Modulation on a Silicon Chip.” Optics Letters 30, no. 21 (2005): 2891. doi:10.1364/OL.30.002891.
Schmidt, Bradley, Vilson Almeida, Christina Manolatou, Stefan Preble, and Michal Lipson. “Nanocavity in a Silicon Waveguide for Ultrasensitive Nanoparticle Detection.” Applied Physics Letters 85, no. 21 (November 23, 2004): 4854–4856. doi:10.1063/1.1819997.