Linked Life Data

20445625

Source:http://linkedlifedata.com/resource/pubmed/id/20445625

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7294
pubmed:dateCreated
2010-5-6
pubmed:abstractText
Recent progress in solid-state quantum information processing has stimulated the search for amplifiers and frequency converters with quantum-limited performance in the microwave range. Depending on the gain applied to the quadratures of a single spatial and temporal mode of the electromagnetic field, linear amplifiers can be classified into two categories (phase sensitive and phase preserving) with fundamentally different noise properties. Phase-sensitive amplifiers use squeezing to reduce the quantum noise, but are useful only in cases in which a reference phase is attached to the signal, such as in homodyne detection. A phase-preserving amplifier would be preferable in many applications, but such devices have not been available until now. Here we experimentally realize a proposal for an intrinsically phase-preserving, superconducting parametric amplifier of non-degenerate type. It is based on a Josephson ring modulator, which consists of four Josephson junctions in a Wheatstone bridge configuration. The device symmetry greatly enhances the purity of the amplification process and simplifies both its operation and its analysis. The measured characteristics of the amplifier in terms of gain and bandwidth are in good agreement with analytical predictions. Using a newly developed noise source, we show that the upper bound on the total system noise of our device under real operating conditions is three times the quantum limit. We foresee applications in the area of quantum analog signal processing, such as quantum non-demolition single-shot readout of qubits, quantum feedback and the production of entangled microwave signal pairs.
pubmed:language
eng
pubmed:journal
pubmed:status
PubMed-not-MEDLINE
pubmed:month
May
pubmed:issn
1476-4687
pubmed:author
pubmed:issnType
Electronic
pubmed:day
6
pubmed:volume
465
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
64-8
pubmed:year
2010
pubmed:articleTitle
Phase-preserving amplification near the quantum limit with a Josephson ring modulator.
pubmed:affiliation
Department of Physics and Applied Physics, Yale University, New Haven, Connecticut 06520-8284, USA. nicolas.bergeal@espci.fr
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, Non-P.H.S., Research Support, Non-U.S. Gov't