May
26
4:10pm 4:10pm

Optical Frequency Transfer with Uncertainty of 10-20

By Long-Sheng Ma, East China Normal University

In the past years, optical atomic clocks have obtained very significant progress with fractional instability and uncertainties of 10-18 level. Using optical clocks, scientists can search for the possible variations of fundamental constant, make a new definition of the unit of time and the application of relativistic geodesy. All this applications need precise transfer optical clock frequency to cover optical and microwave region without degrading their stability, accuracy and coherence. The recent results of optical frequency transfer at East China Normal University will be presented.

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May
26
2:15pm 2:15pm

Strong Coupling of Hybrid and Plasmonic Resonances in Liquid Core Plasmonic Micro Bubble Cavities

By Lei Xu, Fudan University

Thin wall plasmonic micro-bubble resonator, which is a high Q optofluidic silica bubble cavity with a thin Ag film on the inside wall of the bubble, is proposed and fabricated to manipulate coupling between various types of resonant modes by changing its wall thickness and refractive index of the liquid in the core. Coupling of high Q whispering gallery mode/plasmonic resonant mode forms hybrid mode, the hybrid mode can again strongly couple with another interior plasmonic resonant mode in the bubble cavity to achieve tunable high Q plasmonic resonance that can be feasibly accessed by standard tapered fiber coupling. The novel cavity structure therefore provides a unique yet general platform to study plasmonic/photonic, hybrid/plasmonic and plasmonic/plasmonic coupling.

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May
26
11:20am11:20am

Ultrafast Long-distance Quantum Communication with Static Linear Optics

By Peter van Loock, University of Mainz

The first and most common approach to quantum communication across large distances, circumventing the effect of an optical transmission loss exponentially growing with distance, is the quantum repeater. However, the standard quantum repeater based on local quantum memories and two-way classical communication is extremely slow, producing low rates and requiring long-lasting memories.
An obvious remedy here is to replace quantum error detection (as employed in a standard quantum repeater in the form of entanglement purification) by quantum error correction. We shall first give an overview over recent proposals for such an encoded quantum repeater, with a particular emphasis on its ultrafast manifestation using quantum codes against photon losses and one-way classical communication. We will then discuss the possibility of implementing such ultrafast long-distance quantum communication with linear optics. For this purpose, we propose a projection measurement onto encoded Bell states with a static network of linear optical elements.
By increasing the size of the quantum error correction code, both Bell measurement efficiency and photon-loss tolerance can be made arbitrarily high at the same time. As a result, we can show that all-optical quantum communication over large distances with communication rates similar to those of classical communication is possible solely based on local state teleportations using optical sources of encoded Bell states, fixed arrays of beam splitters, and photon detectors. In other words, nonlinear effects are only needed for the generation of the encoded qubits, but not at all for their local processing including error syndrome identification, correction, and state recovery.
We also discuss an extension of our scheme in order to deal in addition with various depolarizing errors, e.g. caused by faulty detectors and resource states, paving the way for ultrafast fault-tolerant long-distance quantum communication with static linear optics.

 

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May
26
9:45am 9:45am

Generation, Characterization and Use of Highly Entangled Quantum Frequency Combs

By Claude Fabre, Université Pierre et Marie Curie

We have determined by pulse shaping techniques and frequency multiplexed homodyne detection the full quantum state of a highly multimode, parametrically generated, frequency comb. This has allowed us to characterize its quantum properties in terms of various types of multipartite entanglement. We will also discuss the possible applications of such a highly entangled state to measurement-based quantum computing.

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May
26
9:00am 9:00am

High Brightness X-ray Sources Driven with Superintense Ultrafast Laser Pulses

By Ruxin Li, Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences

We will introduce recent progress at SIOM in the development of high-brightness x-ray sources driven with intense super-intense ultrafast laser pulses. We have demonstrated a MeV gamma-ray source of high brightness (1022photons/smm2mrad2 per 0.1% bandwidth), based on the Compton scattering of laser accelerated electron beams with laser pulses [1]. Meanwhile, a compact XUV-free electron laser (FEL) at 30nm based on a 0.5GeV level laser electron accelerator is at the final stage of experiments. These x-ray sources are based on the laser wake-field electron accelerators (LWFA) driven by a home-made 5Hz 200TW laser facility [2].

If a LWFA based FEL at XUV regime is successfully implemented, we would move forward to the FELs at sub nm regime. A 10GeV class LWFA would be necessary, which can be driven by a multi PW laser pulses. We will introduce the latest progress of implementing a 10PW laser facility, including the demonstration of a 5PW CPA (chirped pulse amplification) laser amplifier [3] and a 1PW OPCPA (optical parametric chirped pulse amplification) laser amplifier [4].

1. Changhai Yu et al, submitted.

2. Yi Xu et al., Optics and Laser Technology 79, 141(2016).

3. Yuxi Chu et al., High-energy large-aperture Ti:sapphire amplifier for 5 PW laser pulses, Optics Letters 40, 5011 (2015).

4. Lianghong Yu et al., Optimization for high-energy and high-efficiency broadband optical parametric chirped-pulse amplification in LBO near 800 nm, Optics Letters 40, 3412 (2015).

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