Quantum speed limit time: role of coherence
- URL: http://arxiv.org/abs/2202.08078v2
- Date: Sat, 31 Dec 2022 00:37:40 GMT
- Title: Quantum speed limit time: role of coherence
- Authors: K.G. Paulson, Subhashish Banerjee
- Abstract summary: We consider the maximally coherent pure and mixed states as well as multi-qubit $X$ states as initial states.
The role of the non-zero value of initial coherence under information backflow conditions for the non-unital dissipative process is revealed.
The trade-off between mixedness and coherence on the speed limit time reveals the nature of the quantum process the states undergo.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: The minimum evolution time between multi-qubit quantum states is estimated
for non-Markovian quantum channels. We consider the maximally coherent pure and
mixed states as well as multi-qubit $X$ states as initial states and discuss
the impact of initial coherence and the behaviour of coherence on their speed
of evolution for both dephasing and dissipative processes. The role of the
non-zero value of initial coherence under information backflow conditions for
the non-unital dissipative process is revealed by the flow of quantum speed
limit time ($\tau_{QSL}$). The trade-off between mixedness and coherence on the
speed limit time reveals the nature of the quantum process the states undergo.
The complementarity effect between mixedness and coherence is more prominent in
the quantum non-unital dissipation process. The parametric trajectory of speed
limit time vividly depicts the difference in the evolution of pure and mixed
initial states, and this could be used to distinguish between the unital and
non-unital channels studied in this work. Our investigation of quantum speed
limit time on multi-qubit entangled $X$ states reveals that $\tau_{QSL}$ can be
identified as a potential dynamical witness to distinguish multi-qubit states
in the course of evolution.
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