Hello,

I'm a grad student in Dirk Englund's group in EECS; I'll be defending my thesis on the 30th (details below). It would be great to have you there if you can make it. 

Best,
Jake

Title: Photonic quantum computers and communication systems
Presenter: Jake Mower
Time: 2pm, July 30th
Location: 32-124
Committee: Dirk Englund (advisor), Karl Berggren, Jeff Shapiro

Abstract: Quantum information processors have been proposed to solve classically intractable or unsolvable problems in computing, sensing, and secure communication. There has been growing interest in photonic implementations of quantum processors as they offer relatively long coherence lengths, precise state manipulation, and efficient measurement. In this thesis, I first discuss experimental techniques to generate on-chip, photonic quantum processors and then discuss protocols for fast and secure quantum communication.

In the first part of the talk, I will discuss photonic quantum information processing in photonic integrated circuits. I will describe how to combine the outputs of multiple stochastic single-photon sources using a photonic integrated circuit to generate a single, efficient source of single photons [1]. I will then show designs for silicon-based quantum photonic processors that can be programmed to implement a large class of existing quantum algorithms and can lead to quicker testing of new algorithms than was previously possible [2]. Finally, I will present the integration of large numbers of high-efficiency, low-timing jitter single-photon detectors onto a silicon photonic integrated circuit [3].

The second part of the talk will focus on quantum communications. I will describe new protocols for the distribution of a secure cryptographic key using quantum systems. I present a quantum key distribution protocol that uses the robust temporal degree of freedom of entangled photons to enable fast, secure key exchange [4], as well as experimental results for implementing key distribution protocols using silicon photonic integrated circuits.

[1] J. Mower, D. Englund, Phys. Rev. A, 84, 052326 (2011) 
[2] J. Mower., N.C. Harris, G. Steinbrecher, Y. Lahini, D. Englund, to appear in Phys. Rev. A, (2015)
[3] F. Najafi, J. Mower, N.C. Harris, F. Bellei, A. Dane, C. Lee, P. Kharel, F. Marsili, S. Assefa, K.K. Berggren, and D. Englund, Nat. Comm., 6, 5873 (2015)
[4] J. Mower, Z. Zhang, P. Desjardins, C. Lee, J.H. Shapiro, D. Englund, Phys. Rev. A, 87, 062322 (2013)

PhD Candidate
Quantum Photonics Group
Research Lab for Electronics, MIT
Office: 36-585