01036nas a2200181 4500008004100000245006600041210006500107260001400172490000700186520050100193100002500694700001700719700002100736700001800757700002300775700001900798856003700817 2010 eng d00aAdiabatic preparation of many-body states in optical lattices0 aAdiabatic preparation of manybody states in optical lattices c2010/6/220 v813 a We analyze a technique for the preparation of low entropy many body states of
atoms in optical lattices based on adiabatic passage. In particular, we show
that this method allows preparation of strongly correlated states as stable
highest energy states of Hamiltonians that have trivial ground states. As an
example, we analyze the generation of antiferromagnetically ordered states by
adiabatic change of a staggered field acting on the spins of bosonic atoms with
ferromagnetic interactions.
1 aSorensen, Anders, S.1 aAltman, Ehud1 aGullans, Michael1 aPorto, J., V.1 aLukin, Mikhail, D.1 aDemler, Eugene uhttp://arxiv.org/abs/0906.2567v301226nas a2200181 4500008004100000245008600041210006900127260001400196490000700210520065700217100002300874700001700897700002500914700002000939700002500959700002300984856003701007 2010 eng d00aFast Entanglement Distribution with Atomic Ensembles and Fluorescent Detection
0 aFast Entanglement Distribution with Atomic Ensembles and Fluores c2010/2/120 v813 a Quantum repeaters based on atomic ensemble quantum memories are promising
candidates for achieving scalable distribution of entanglement over long
distances. Recently, important experimental progress has been made towards
their implementation. However, the entanglement rates and scalability of
current approaches are limited by relatively low retrieval and single-photon
detector efficiencies. We propose a scheme, which makes use of fluorescent
detection of stored excitations to significantly increase the efficiency of
connection and hence the rate. Practical performance and possible experimental
realizations of the new protocol are discussed.
1 aBrask, Jonatan, B.1 aJiang, Liang1 aGorshkov, Alexey, V.1 aVuletic, Vladan1 aSorensen, Anders, S.1 aLukin, Mikhail, D. uhttp://arxiv.org/abs/0907.3839v201383nas a2200157 4500008004100000245010900041210006900150260001300219490000700232520085500239100002501094700002101119700002301140700002501163856003701188 2008 eng d00aPhoton storage in Lambda-type optically dense atomic media. IV. Optimal control using gradient ascent
0 aPhoton storage in Lambdatype optically dense atomic media IV Opt c2008/4/40 v773 a We use the numerical gradient ascent method from optimal control theory to
extend efficient photon storage in Lambda-type media to previously inaccessible
regimes and to provide simple intuitive explanations for our optimization
techniques. In particular, by using gradient ascent to shape classical control
pulses used to mediate photon storage, we open up the possibility of high
efficiency photon storage in the non-adiabatic limit, in which analytical
solutions to the equations of motion do not exist. This control shaping
technique enables an order-of-magnitude increase in the bandwidth of the
memory. We also demonstrate that the often discussed connection between time
reversal and optimality in photon storage follows naturally from gradient
ascent. Finally, we discuss the optimization of controlled reversible
inhomogeneous broadening.
1 aGorshkov, Alexey, V.1 aCalarco, Tommaso1 aLukin, Mikhail, D.1 aSorensen, Anders, S. uhttp://arxiv.org/abs/0710.2698v200984nas a2200181 4500008004100000245005700041210005700098260001400155490000700169520043900176100002000615700002500635700002400660700002500684700002300709700002600732856004400758 2007 eng d00aOptimal control of light pulse storage and retrieval0 aOptimal control of light pulse storage and retrieval c2007/6/150 v983 a We demonstrate experimentally a procedure to obtain the maximum efficiency
for the storage and retrieval of light pulses in atomic media. The procedure
uses time reversal to obtain optimal input signal pulse-shapes. Experimental
results in warm Rb vapor are in good agreement with theoretical predictions and
demonstrate a substantial improvement of efficiency. This optimization
procedure is applicable to a wide range of systems.
1 aNovikova, Irina1 aGorshkov, Alexey, V.1 aPhillips, David, F.1 aSorensen, Anders, S.1 aLukin, Mikhail, D.1 aWalsworth, Ronald, L. uhttp://arxiv.org/abs/quant-ph/0702266v101698nas a2200157 4500008004100000245008300041210006900124260001300193490000700206520119400213100002501407700001601432700002301448700002501471856004401496 2007 eng d00aPhoton storage in Lambda-type optically dense atomic media. I. Cavity model
0 aPhoton storage in Lambdatype optically dense atomic media I Cavi c2007/9/70 v763 a In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we
used a universal physical picture to optimize and demonstrate equivalence
between a wide range of techniques for storage and retrieval of photon wave
packets in Lambda-type atomic media in free space, including the adiabatic
reduction of the photon group velocity, pulse-propagation control via
off-resonant Raman techniques, and photon-echo-based techniques. In the present
paper, we perform the same analysis for the cavity model. In particular, we
show that the retrieval efficiency is equal to C/(1+C) independent of the
retrieval technique, where C is the cooperativity parameter. We also derive the
optimal strategy for storage and, in particular, demonstrate that at any
detuning one can store, with the optimal efficiency of C/(1+C), any smooth
input mode satisfying T C gamma >> 1 and a certain class of resonant input
modes satisfying T C gamma ~ 1, where T is the duration of the input mode and 2
gamma is the transition linewidth. In the two subsequent papers of the series,
we present the full analysis of the free-space model and discuss the effects of
inhomogeneous broadening on photon storage.
1 aGorshkov, Alexey, V.1 aAndre, Axel1 aLukin, Mikhail, D.1 aSorensen, Anders, S. uhttp://arxiv.org/abs/quant-ph/0612082v201505nas a2200157 4500008004100000245008800041210006900129260001300198490000700211520099600218100002501214700001601239700002301255700002501278856004401303 2007 eng d00aPhoton storage in Lambda-type optically dense atomic media. II. Free-space model
0 aPhoton storage in Lambdatype optically dense atomic media II Fre c2007/9/70 v763 a In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)], we
presented a universal physical picture for describing a wide range of
techniques for storage and retrieval of photon wave packets in Lambda-type
atomic media in free space, including the adiabatic reduction of the photon
group velocity, pulse-propagation control via off-resonant Raman techniques,
and photon-echo based techniques. This universal picture produced an optimal
control strategy for photon storage and retrieval applicable to all approaches
and yielded identical maximum efficiencies for all of them. In the present
paper, we present the full details of this analysis as well some of its
extensions, including the discussion of the effects of non-degeneracy of the
two lower levels of the Lambda system. The analysis in the present paper is
based on the intuition obtained from the study of photon storage in the cavity
model in the preceding paper [Gorshkov et al., Phys. Rev. A 76, 033804 (2007)].
1 aGorshkov, Alexey, V.1 aAndre, Axel1 aLukin, Mikhail, D.1 aSorensen, Anders, S. uhttp://arxiv.org/abs/quant-ph/0612083v201814nas a2200157 4500008004100000245010800041210006900149260001300218490000700231520128500238100002501523700001601548700002301564700002501587856004401612 2007 eng d00aPhoton storage in Lambda-type optically dense atomic media. III. Effects of inhomogeneous broadening
0 aPhoton storage in Lambdatype optically dense atomic media III Ef c2007/9/70 v763 a In a recent paper [Gorshkov et al., Phys. Rev. Lett. 98, 123601 (2007)] and
in the two preceding papers [Gorshkov et al., Phys. Rev. A 76, 033804 (2007);
76, 033805 (2007)], we used a universal physical picture to optimize and
demonstrate equivalence between a wide range of techniques for storage and
retrieval of photon wave packets in homogeneously broadened Lambda-type atomic
media, including the adiabatic reduction of the photon group velocity,
pulse-propagation control via off-resonant Raman techniques, and
photon-echo-based techniques. In the present paper, we generalize this
treatment to include inhomogeneous broadening. In particular, we consider the
case of Doppler-broadened atoms and assume that there is a negligible
difference between the Doppler shifts of the two optical transitions. In this
situation, we show that, at high enough optical depth, all atoms contribute
coherently to the storage process as if the medium were homogeneously
broadened. We also discuss the effects of inhomogeneous broadening in solid
state samples. In this context, we discuss the advantages and limitations of
reversing the inhomogeneous broadening during the storage time, as well as
suggest a way for achieving high efficiencies with a nonreversible
inhomogeneous profile.
1 aGorshkov, Alexey, V.1 aAndre, Axel1 aLukin, Mikhail, D.1 aSorensen, Anders, S. uhttp://arxiv.org/abs/quant-ph/0612084v201151nas a2200169 4500008004100000245006500041210006500106260001400171490000700185520063000192100002500822700001600847700002600863700002500889700002300914856004400937 2007 eng d00aUniversal Approach to Optimal Photon Storage in Atomic Media0 aUniversal Approach to Optimal Photon Storage in Atomic Media c2007/3/190 v983 a We present a universal physical picture for describing storage and retrieval
of photon wave packets in a Lambda-type atomic medium. This physical picture
encompasses a variety of different approaches to pulse storage ranging from
adiabatic reduction of the photon group velocity and pulse-propagation control
via off-resonant Raman fields to photon-echo based techniques. Furthermore, we
derive an optimal control strategy for storage and retrieval of a photon wave
packet of any given shape. All these approaches, when optimized, yield
identical maximum efficiencies, which only depend on the optical depth of the
medium.
1 aGorshkov, Alexey, V.1 aAndre, Axel1 aFleischhauer, Michael1 aSorensen, Anders, S.1 aLukin, Mikhail, D. uhttp://arxiv.org/abs/quant-ph/0604037v3