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Erschienen in: Quantum Information Processing 4/2021

01.04.2021

Strong\(^*\) convergence of quantum channels

verfasst von: M. E. Shirokov

Erschienen in: Quantum Information Processing | Ausgabe 4/2021

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Abstract

Recently, the existence of a strongly converging sequence of quantum channels that cannot be represented a reduction of a sequence of unitary channels strongly converging to a unitary channel was shown. In this work, we obtain several characterizations of sequences of quantum channels that have the above representation. The corresponding convergence is called the strong\(^*\) convergence, since we have found that it is related to the convergence of selective Stinespring isometries in the strong\(^*\) operator topology. We present the arguments showing that the strong\(^*\) convergence is a proper, physically motivated type of convergence of infinite-dimensional quantum channels. Some properties of the strong\(^*\) convergence of quantum channels are considered. It is shown that for Bosonic Gaussian channels the strong\(^*\) convergence coincides with the strong convergence.

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Fußnoten
1
It seems reasonable to assume that all physical perturbations of a unitary channel \(\rho \mapsto U\rho U^*\) are properly described by continuous deformations of the unitary U in the strong operator topology (coinciding in this case with other basic operator topologies excepting the norm topology [12]).
 
2
\(s\text {-}\!\lim \nolimits _{n\rightarrow \infty } X_n=X_0\) denotes the convergence of a sequence \(\{X_n\}\) to an operator \(X_0\) in the strong operator topology.
 
3
\({\Phi }^*\) is the dual map to the channel \({\Phi }\) defined by relation (6).
 
4
We write \(I_X\) and \(\mathrm {Id}_X\) instead of \(I_{{\mathcal {H}}_X}\) and \(\mathrm {Id}_{{\mathcal {H}}_X}\) (where \(X=A,B,..\)) to simplify notation.
 
5
Similar statements for the strong convergence are proved explicitly in [9].
 
6
I am grateful to R.F.Werner for pointing me this result and its proof in the case \({\Phi }_0=\mathrm {Id}_A\).
 
7
It means that \(s\text {-}\!\lim \nolimits _{n\rightarrow \infty } W_n=P_0\) and \(s\text {-}\!\lim \nolimits _{n\rightarrow \infty } W^*_n=P_0\) [12].
 
8
Gaussian unitary channel is a channel \(\rho \mapsto U_T\rho U^*_T\), where \(U_T\) is the canonical unitary corresponding to a symplectic transformation T [1, Ch.12].
 
Literatur
1.
Zurück zum Zitat Holevo, A.S.: Quantum Systems, Channels, Information. A Mathematical Introduction. DeGruyter, Berlin (2012)CrossRefMATH Holevo, A.S.: Quantum Systems, Channels, Information. A Mathematical Introduction. DeGruyter, Berlin (2012)CrossRefMATH
2.
Zurück zum Zitat Wilde, M.M.: Quantum Information Theory. Cambridge University Press, Cambridge (2013)CrossRefMATH Wilde, M.M.: Quantum Information Theory. Cambridge University Press, Cambridge (2013)CrossRefMATH
3.
Zurück zum Zitat Kraus, K.: States, Effects and Operations: Fundamental Notions of Quantum Theory. Springer, Berlin (1983)CrossRefMATH Kraus, K.: States, Effects and Operations: Fundamental Notions of Quantum Theory. Springer, Berlin (1983)CrossRefMATH
4.
Zurück zum Zitat Aharonov, D., Kitaev, A, Nisan, N.: Quantum circuits with mixed states. In: Proceedings of the 30th STOC, pp. 20–30. ACM Press (1998) Aharonov, D., Kitaev, A, Nisan, N.: Quantum circuits with mixed states. In: Proceedings of the 30th STOC, pp. 20–30. ACM Press (1998)
5.
Zurück zum Zitat Paulsen, V.I.: Completely Bounded Maps and Operator Algebras. Cambridge Studies in Advanced Mathematics. Cambridge University Press, Cambridge (2002) Paulsen, V.I.: Completely Bounded Maps and Operator Algebras. Cambridge Studies in Advanced Mathematics. Cambridge University Press, Cambridge (2002)
6.
7.
Zurück zum Zitat Winter, A.: Energy-Constrained Diamond Norm with Applications to the Uniform Continuity of Continuous Variable Channel Capacities. arXiv:1712.10267 [quant-ph] Winter, A.: Energy-Constrained Diamond Norm with Applications to the Uniform Continuity of Continuous Variable Channel Capacities. arXiv:​1712.​10267 [quant-ph]
8.
Zurück zum Zitat Shirokov, M.E., Holevo, A.S.: On approximation of infinite dimensional quantum channels. Probl. Inf. Transm. 44(2), 3–22 (2008)MathSciNetCrossRefMATH Shirokov, M.E., Holevo, A.S.: On approximation of infinite dimensional quantum channels. Probl. Inf. Transm. 44(2), 3–22 (2008)MathSciNetCrossRefMATH
9.
Zurück zum Zitat Wilde, M.M.: Strong and uniform convergence in the teleportation simulation of bosonic Gaussian channels. Phys. Rev. A 97(6), 062305 (2018)ADSCrossRef Wilde, M.M.: Strong and uniform convergence in the teleportation simulation of bosonic Gaussian channels. Phys. Rev. A 97(6), 062305 (2018)ADSCrossRef
10.
Zurück zum Zitat Shirokov, M.E.: Strong convergence of quantum channels: continuity of the Stinespring dilation and discontinuity of the unitary dilation. J. Math. Phys. 61, 082204 (2020)ADSMathSciNetCrossRefMATH Shirokov, M.E.: Strong convergence of quantum channels: continuity of the Stinespring dilation and discontinuity of the unitary dilation. J. Math. Phys. 61, 082204 (2020)ADSMathSciNetCrossRefMATH
11.
Zurück zum Zitat Kretschmann, D., Schlingemann, D., Werner, R.F.: A continuity theorem for Stinespring’s dilation. J. Funct. Anal. 255(8), 1889–1904 (2008)MathSciNetCrossRefMATH Kretschmann, D., Schlingemann, D., Werner, R.F.: A continuity theorem for Stinespring’s dilation. J. Funct. Anal. 255(8), 1889–1904 (2008)MathSciNetCrossRefMATH
12.
Zurück zum Zitat Bratteli, O., Robinson, D.W.: Operators Algebras and Quantum Statistical Mechanics, vol. I. Springer, New York (1979)CrossRefMATH Bratteli, O., Robinson, D.W.: Operators Algebras and Quantum Statistical Mechanics, vol. I. Springer, New York (1979)CrossRefMATH
13.
Zurück zum Zitat Stinespring, W.F.: Positive functions on \(C^*\)-algebras. Proc. Am. Math. Soc. 6(2), 211–216 (1955)MathSciNet Stinespring, W.F.: Positive functions on \(C^*\)-algebras. Proc. Am. Math. Soc. 6(2), 211–216 (1955)MathSciNet
14.
Zurück zum Zitat Holevo, A.S.: On complementary channels and the additivity problem. Probab. Theory Appl. 51, 133–143 (2005)MathSciNet Holevo, A.S.: On complementary channels and the additivity problem. Probab. Theory Appl. 51, 133–143 (2005)MathSciNet
15.
Zurück zum Zitat Reed, M., Simon, B.: Methods of Modern Mathematical Physics. Functional Analysis, vol. I. Academic Press Inc. (1980) Reed, M., Simon, B.: Methods of Modern Mathematical Physics. Functional Analysis, vol. I. Academic Press Inc. (1980)
17.
Zurück zum Zitat Weedbrook, C., Pirandola, S., Garcia-Patron, R., Cerf, N.J., Ralph, T.C., Shapiro, J.H., Lloyd, S.: Gaussian quantum information. Rev. Mod. Phys. 84, 621 (2012)ADSCrossRef Weedbrook, C., Pirandola, S., Garcia-Patron, R., Cerf, N.J., Ralph, T.C., Shapiro, J.H., Lloyd, S.: Gaussian quantum information. Rev. Mod. Phys. 84, 621 (2012)ADSCrossRef
19.
Zurück zum Zitat Caruso, F., Eisert, J., Giovannetti, V., Holevo, A.S.: Multi-mode bosonic Gaussian channels. New J. Phys. 10, 083030 (33pp) (2008) Caruso, F., Eisert, J., Giovannetti, V., Holevo, A.S.: Multi-mode bosonic Gaussian channels. New J. Phys. 10, 083030 (33pp) (2008)
20.
Zurück zum Zitat Caruso, F., Eisert, J., Giovannetti, V., Holevo, A.S.: The optimal unitary dilation for bosonic Gaussian channels. Phys. Rev. A 84, 022306 (2011)ADSCrossRef Caruso, F., Eisert, J., Giovannetti, V., Holevo, A.S.: The optimal unitary dilation for bosonic Gaussian channels. Phys. Rev. A 84, 022306 (2011)ADSCrossRef
Metadaten
Titel
Strong convergence of quantum channels
verfasst von
M. E. Shirokov
Publikationsdatum
01.04.2021
Verlag
Springer US
Erschienen in
Quantum Information Processing / Ausgabe 4/2021
Print ISSN: 1570-0755
Elektronische ISSN: 1573-1332
DOI
https://doi.org/10.1007/s11128-021-03087-z

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