33,865 research outputs found
Optical wavelength conversion of quantum states with optomechanics
An optomechanical interface that converts quantum states between optical
fields with distinct wavelengths is proposed. A mechanical mode couples to two
optical modes via radiation pressure and mediates the quantum state mapping
between the two optical modes. A sequence of optomechanical pulses
enables state-swapping between optical and mechanical states as well as the
cooling of the mechanical mode. Theoretical analysis shows that high fidelity
conversion can be realized for states with small photon numbers in systems with
experimentally achievable parameters. The pulsed conversion process also makes
it possible to maintain high conversion fidelity at elevated bath temperatures.Comment: 4 pages, 4 figures, Fig. 4 looks weird (possible latex style problem
Adiabatic State Conversion and Pulse Transmission in Optomechanical Systems
Optomechanical systems with strong coupling can be a powerful medium for
quantum state engineering. Here, we show that quantum state conversion between
cavity modes with different wavelengths can be realized with high fidelity by
adiabatically varying the effective optomechanical couplings. The fidelity for
the conversion of gaussian states is derived by solving the Langevin equation
in the adiabatic limit. We also show that photon pulses can be transmitted
between input-output channels with different wavelengths via the effective
optomechanical couplings and the output pulse shape can also be manipulated.Comment: 5 pages, 2 figures. Supplementary Materials at
http://prl.aps.org/supplemental/PRL/v108/i15/e15360
Efficiency in index options markets and trading in stock baskets
Researchers have reported mispricing in index options markets. This study further examines the efficiency of the S&P 500 index options market by testing theoretical pricing relationships implied by no-arbitrage conditions. The effect of a traded stock basket, Standard and Poor's Depository Receipts (SPDRs), on the link between index and options markets is also examined. Pricing efficiency within options markets improves, and the evidence supports the hypothesis that a stock basket enhances the connection between markets. However, when transactions costs and short sales constraints are included, very few violations of the pricing relationships are reported.Options (Finance) ; Stock - Prices
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