An entangled state of a two-particle system is a quantum state that cannot be separated--it cannot be written as the product of states of the individual particles. One way to tell if a system is entangled is to use it to violate a Bell inequality (such as the Clauser-Horne-Shimony-Holt, CHSH, inequality), because entanglement is necessary to violate these inequalities. However, there are other, more efficient measurements that determine whether or not a system is entangled; an operator that corresponds to such a measurement is referred to as an entanglement witness. We present the theory of witness operators, and an undergraduate experiment that measures an entanglement witness for the joint polarization state of two photons. We are able to produce states for which the expectation value of the witness operator is entangled by more than 160 standard deviations.
2015 Conference on Laboratory Instruction Beyond the First Year of College
Part of the BFY Conference series
College Park, MD: July 22-24, 2015
Pages 12-15
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<a href="https://www.compadre.org/quantum/items/detail.cfm?ID=13795">Beck, Marisol, and Mark Beck. "Witnessing Entanglement." Paper presented at the 2015 Conference on Laboratory Instruction Beyond the First Year of College, College Park, MD, July 22-24, 2015.</a>
M. Beck and M. Beck, , presented at the 2015 Conference on Laboratory Instruction Beyond the First Year of College, College Park, MD, 2015, WWW Document, (https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215).
M. Beck and M. Beck, Witnessing Entanglement, presented at the 2015 Conference on Laboratory Instruction Beyond the First Year of College, College Park, MD, 2015, <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215>.
Beck, M., & Beck, M. (2015, July 22-24). Witnessing Entanglement. Paper presented at 2015 Conference on Laboratory Instruction Beyond the First Year of College, College Park, MD. Retrieved October 7, 2024, from https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215
Beck, Marisol, and Mark Beck. "Witnessing Entanglement." Paper presented at the 2015 Conference on Laboratory Instruction Beyond the First Year of College, College Park, MD, July 22-24, 2015. https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215 (accessed 7 October 2024).
Beck, Marisol, and Mark Beck. "Witnessing Entanglement." 2015 Conference on Laboratory Instruction Beyond the First Year of College. College Park, MD: 2015. 12-15 of BFY Conference. 7 Oct. 2024 <https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215>.
@inproceedings{
Author = "Marisol Beck and Mark Beck",
Title = {Witnessing Entanglement},
BookTitle = {2015 Conference on Laboratory Instruction Beyond the First Year of College},
Pages = {12-15},
Address = {College Park, MD},
Series = {BFY Conference},
Month = {July 22-24},
Year = {2015}
}
%A Marisol Beck %A Mark Beck %T Witnessing Entanglement %S BFY Conference %D July 22-24 2015 %P 12-15 %C College Park, MD %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215 %O 2015 Conference on Laboratory Instruction Beyond the First Year of College %O July 22-24 %O application/pdf
%0 Conference Proceedings %A Beck, Marisol %A Beck, Mark %D July 22-24 2015 %T Witnessing Entanglement %B 2015 Conference on Laboratory Instruction Beyond the First Year of College %C College Park, MD %P 12-15 %S BFY Conference %8 July 22-24 %U https://www.compadre.org/Repository/document/ServeFile.cfm?ID=13795&DocID=4215
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