Why we need universal-not gate in quantum computing

Assignment Help Physics

Reference no: EM13972928

The universal-NOT gate in quantum computing is an operation which maps every point on the Bloch sphere to its antipodal point (see Buzek et al, Phys. Rev. A 60, R2626-R2629). In general, a single qubit quantum state, |??=α|0?+β|1? will be mapped to β∗|0?-α∗|1?. This operation is not unitary (in fact it is anti-unitary) and so is not something that can be implemented deterministically on a quantum computer.

Optimal approximations to such gates drew quite a lot of interest about 10 years ago (see for example this Nature paper which presents an experimental realization of an optimal approximation).

What has been puzzling me, and what I cannot find in any of the introductions to these papers, is why one would ever want such a gate. Is it actually useful for anything? Moreover, why would one want an approximation, when there are other representations of SU(2) for which there is a unitary operator which anti-commutes with all of the generators?

This question may seem vague, but I believe it has a concrete answer. There presumable is one or more strong reasons why we might want such an operator and I am simply not seeing them (or finding them). If anyone could enlighten me, it would be much appreciated.

Reference no: EM13972928

Questions Cloud

Present value index for investment : In addition to the foregoing information, use the following data in determining the acceptability in this situation: The present value index for this investment is:

Prepare all the journal entries that mars corporation : Prepare all the journal entries that Mars Corporation would make related to this bond issue through January 1, 2015. Be sure to indicate the date on which the entries would be made.

Replenishment of the petty cash fund : On March 20, Garber's petty cash fund of $100 is replenished when the fund contains $47 in cash and receipts for postage $31, supplies $16, and travel expense $6. Prepare the journal entry to record the replenishment of the petty cash fund.

Explain the company''s position on the eeoc claim. : Write a 2-3-page paper in Word format based on EEOC recommendations for your position statement. Apply APA standards to citation of sources. Use the following file naming convention:

Why we need universal-not gate in quantum computing : The universal-NOT gate in quantum computing is an operation which maps every point on the Bloch sphere to its antipodal point (see Buzek et al, Phys. Rev. A 60, R2626-R2629). In general, a single qubit quantum state, |??=α|0?+β|1? will be mapped t..

Brief summary of the history of islam : Describe significant differences and similarities in how the branches of Islam (Sunni, Shiite, and Sufi) practice their traditions.

Determine the payback period : Norman uses straight-line depreciation. Expected revenue is $25,000 per year. Assume that depreciation is the only expense associated with this investment. Required a. Determine the payback period. (Round your answer to 1 decimal place.) (years)

How have these relationships evolved over time : Discuss how politicians have traditionally benefited from partnerships with organized crime and how criminal figures have benefited from a reciprocal relationship

User Account

All Pages