Relative Phase Change During Quantum Operations

Relative Phase Change During Quantum Operations Quantum operations represented by completely positive maps encompass many physical processes and have been very powerful in describing quantum computation and information processing tasks. We introduce the notion of relative phase change for a quantum system undergoing a quantum operation. We find that the relative phase shift of a system not only depends on the initial state of the system, but also depends on the initial state of an ancilla with which it might have interacted in the past. The relative phase change during a sequence of quantum operations is shown to be non-additive in nature. This property can attribute a “memory” to a quantum channel. Also the notion of relative phase shift helps us to define what we call “in-phase quantum channels.” We will present the relative phase shifts for a qubit undergoing both a depolarizing channel and complete randomization, and discuss their implications. http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Quantum Information Processing Springer Journals

Relative Phase Change During Quantum Operations

Loading next page...
 
/lp/springer_journal/relative-phase-change-during-quantum-operations-W02Wvb5jKo
Publisher
Kluwer Academic Publishers-Plenum Publishers
Copyright
Copyright © 2003 by Plenum Publishing Corporation
Subject
Physics; Quantum Information Technology, Spintronics; Quantum Computing; Data Structures, Cryptology and Information Theory; Quantum Physics; Mathematical Physics
ISSN
1570-0755
eISSN
1573-1332
D.O.I.
10.1023/A:1025847609264
Publisher site
See Article on Publisher Site

Abstract

Quantum operations represented by completely positive maps encompass many physical processes and have been very powerful in describing quantum computation and information processing tasks. We introduce the notion of relative phase change for a quantum system undergoing a quantum operation. We find that the relative phase shift of a system not only depends on the initial state of the system, but also depends on the initial state of an ancilla with which it might have interacted in the past. The relative phase change during a sequence of quantum operations is shown to be non-additive in nature. This property can attribute a “memory” to a quantum channel. Also the notion of relative phase shift helps us to define what we call “in-phase quantum channels.” We will present the relative phase shifts for a qubit undergoing both a depolarizing channel and complete randomization, and discuss their implications.

Journal

Quantum Information ProcessingSpringer Journals

Published: Oct 18, 2004

References

You’re reading a free preview. Subscribe to read the entire article.


DeepDyve is your
personal research library

It’s your single place to instantly
discover and read the research
that matters to you.

Enjoy affordable access to
over 12 million articles from more than
10,000 peer-reviewed journals.

All for just $49/month

Explore the DeepDyve Library

Unlimited reading

Read as many articles as you need. Full articles with original layout, charts and figures. Read online, from anywhere.

Stay up to date

Keep up with your field with Personalized Recommendations and Follow Journals to get automatic updates.

Organize your research

It’s easy to organize your research with our built-in tools.

Your journals are on DeepDyve

Read from thousands of the leading scholarly journals from SpringerNature, Elsevier, Wiley-Blackwell, Oxford University Press and more.

All the latest content is available, no embargo periods.

See the journals in your area

DeepDyve Freelancer

DeepDyve Pro

Price
FREE
$49/month

$360/year
Save searches from Google Scholar, PubMed
Create lists to organize your research
Export lists, citations
Read DeepDyve articles
Abstract access only
Unlimited access to over
18 million full-text articles
Print
20 pages/month
PDF Discount
20% off