Publications


Qubits, qutrits, and ququads stored in single photons from an atom-cavity system

ADVANCES IN PHOTONICS OF QUANTUM COMPUTING, MEMORY, AND COMMUNICATION VIII 9377 (2015)

A Holleczek, O Barter, G Langfahl-Klabes, A Kuhn


Cavity Induced Interfacing of Atoms and Light

ArXiv (2015)

A Kuhn

This chapter introduces cavity-based light-matter quantum interfaces, with a single atom or ion in strong coupling to a high-finesse optical cavity. We discuss the deterministic generation of indistinguishable single photons from these systems; the atom-photon entanglement intractably linked to this process; and the information encoding using spatio-temporal modes within these photons. Furthermore, we show how to establish a time-reversal of the aforementioned emission process to use a coupled atom-cavity system as a quantum memory. Along the line, we also discuss the performance and characterisation of cavity photons in elementary linear-optics arrangements with single beam splitters for quantum-homodyne measurements.


Fast algorithms for generating binary holograms

ArXiv (2014)

D Stuart, O Barter, A Kuhn

We describe three algorithms for generating binary-valued holograms. Our methods are optimised for producing large arrays of tightly focussed optical tweezers for trapping particles. Binary-valued holograms allow us to use a digital mirror device (DMD) as the display element, which is much faster than other alternatives. We describe how our binary amplitude holograms can be used to correct for phase errors caused by optical aberrations. Furthermore, we compare the speed and accuracy of the algorithms for both periodic and arbitrary arrangements of traps, which allows one to choose the ideal scheme depending on the circumstances.


Photonic qubits, qutrits and ququads accurately prepared and delivered on demand

New Journal of Physics 15 (2013) 053007

PBR Nisbet-Jones, J Dilley, A Holleczek, O Barter, A Kuhn

Reliable encoding of information in quantum systems is crucial to all approaches to quantum information processing or communication. This applies in particular to photons used in linear optics quantum computing, which is scalable provided a deterministic single-photon emission and preparation is available. Here, we show that narrowband photons deterministically emitted from an atom–cavity system fulfil these requirements. Within their 500 ns coherence time, we demonstrate a subdivision into d time bins of various amplitudes and phases, which we use for encoding arbitrary qu-d-its. The latter is done deterministically with a fidelity >95% for qubits, verified using a newly developed time-resolved quantum-homodyne method.


Quantum networking with time-bin encoded qu-d-its using single photons emitted on demand from an atom-cavity system

Optics InfoBase Conference Papers (2013)

A Holleczek, O Barter, PBR Nisbet-Jones, J Dilley, A Kuhn


Single Emitters in Isolated Quantum Systems

Experimental Methods in the Physical Sciences 45 (2013) 467-539

GS Solomon, C Santori, A Kuhn


Quantum networking with time-bin encoded qu-d-its using single photons emitted on demand from an atom-cavity system

2013 Conference on Lasers and Electro-Optics Europe and International Quantum Electronics Conference, CLEO/Europe-IQEC 2013 (2013)

A Holleczek, O Barter, PBR Nisbet-Jones, J Dilley, A Kuhn

One of today's challenges to realize computing based on quantum mechanics is to reliably and scalably encode information in quantum systems. This is particularly crucial when dealing with promising approaches such as linear optics quantum computing (LOQC) in photonic circuits [1,2]. Although this method is in principle scalable, in practice it is limited by the probabilistic nature of spontaneous parametric down-conversion (SPDC) sources used to seed the circuits. © 2013 IEEE.


Single-photon absorption in coupled atom-cavity systems

PHYSICAL REVIEW A 85 (2012) ARTN 023834

J Dilley, P Nisbet-Jones, BW Shore, A Kuhn


Control and manipulation of cold atoms in optical tweezers

NEW JOURNAL OF PHYSICS 14 (2012) ARTN 073051

C Muldoon, L Brandt, J Dong, D Stuart, E Brainis, M Himsworth, A Kuhn


Three Dimensional Raman Cooling using Velocity Selective Rapid Adiabatic Passage

Chapter in ,

A Kuhn, H Perrin, W Hänsel, C Salomon

We present a new and efficient implementation of Raman cooling of trapped atoms. It uses Raman pulses with an appropriate frequency chirp to realize a velocity selective excitation through a rapid adiabatic passage. This method allows to address in a single pulse a large number of non zero atomic velocity classes and it produces a nearly unity transfer efficiency. We demonstrate this cooling method using cesium atoms in a far-detuned crossed dipole trap. Three-dimensional cooling of $1 \times 10^{5}$ atoms down to $2 \mu$K is performed in 100 ms. In this preliminary experiment the final atomic density is $1.3\times 10^{12}$ at/cm$^3$ (within a factor of 2) and the phase-space density increase over the uncooled sample is 20. Numerical simulations indicate that temperatures below the single photon recoil temperature should be achievable with this method.


EIT-based quantum memory for single photons from cavity-QED

APPLIED PHYSICS B-LASERS AND OPTICS 103 (2011) 579-589

M Himsworth, P Nisbet, J Dilley, G Langfahl-Klabes, A Kuhn


Highly efficient source for indistinguishable single photons of controlled shape

NEW JOURNAL OF PHYSICS 13 (2011) ARTN 103036

PBR Nisbet-Jones, J Dilley, D Ljunggren, A Kuhn


Quantum memories for single photons from cavity-QED

Optics InfoBase Conference Papers (2011)

A Kuhn, P Nisbet, J Dilley, G Langfahl-Klabes, M Himsworth


Spatial light modulators for the manipulation of individual atoms

APPLIED PHYSICS B-LASERS AND OPTICS 102 (2011) 443-450

L Brandt, C Muldoon, T Thiele, J Dong, E Brainis, A Kuhn


Cavity-based single-photon sources

CONTEMPORARY PHYSICS 51 (2010) 289-313

A Kuhn, D Ljunggren


Implementation of atom-photon interfaces for quantum networking

Optics InfoBase Conference Papers (2010)

L Brandt, C Muldoon, T Thiele, J Dilley, P Nisbet, G Langfahl-Klabes, A Kuhn

We present two schemes for interfacing and manipulating individual atoms: One involves an array of dipole-traps using a spatial light modulator. The other implements cavitybased single photon generation combined with photon storage. © 2010 Optical Society of America.


Single photons made-to-measure

NEW JOURNAL OF PHYSICS 12 (2010) ARTN 063024

GS Vasilev, D Ljunggren, A Kuhn


Implementations of atom-photon interfaces for quantum networking

Optics InfoBase Conference Papers (2009)

PBR Nisbet, J Dilley, G Langfahl-Klabes, D Ljunggren, G Vasilev, A Kuhn


Optical Tweezers for manipulating single atoms

Optics InfoBase Conference Papers (2009)

L Brandt, C Muldoon, E Brainis, A Kuhn


Implementations of atom-photon interfaces for quantum networking

Optics InfoBase Conference Papers (2009)

PBR Nisbet, J Dille, G Langfahl-Klabes, D Ljunggren, G Vasilev, A Kuhn