Deriving mixed state of light field by partial tracing pure state in higher dimension

• Published in: Physica A Vol. 623; p. 128809
• Main Authors: Wan, Zhi-Long, Yuan, Hong-Chun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 01.08.2023
• Subjects: New density operator; Partial trace; Wigner function; New density operator; Partial trace; Wigner function

In this paper, we show that by partial tracing the pure state in higher dimension one can deduce the mixed state of light field. In this paper the pure state in higher dimension is a three-mode squeezed state S23σS31τ000000S31−1τS23−1σ, while the mixed state’s density operator is sech2σsech2τea2†a3†...