Limits...
Examining non-locality and quantum coherent dynamics induced by a common reservoir.

Chen GY, Chen SL, Li CM, Chen YN - Sci Rep (2013)

Bottom Line: Here, we propose to use the steering inequality to examine the non-locality induced by a common reservoir.Compared with the Bell inequality, we find that the steering inequality has a better tolerance for examining non-locality.In view of the dynamic nature of the entangling process, we also propose to observe the quantum coherent dynamics by using the Leggett-Garg inequalities.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, National Chung Hsing University, Taichung 402, Taiwan.

ABSTRACT
If two identical emitters are coupled to a common reservoir, entanglement can be generated during the decay process. When using Bell's inequality to examine the non-locality, however, it is possible that the bound cannot be violated in some cases. Here, we propose to use the steering inequality to examine the non-locality induced by a common reservoir. Compared with the Bell inequality, we find that the steering inequality has a better tolerance for examining non-locality. In view of the dynamic nature of the entangling process, we also propose to observe the quantum coherent dynamics by using the Leggett-Garg inequalities. We also suggest a feasible scheme, which consists of two quantum dots coupled to nanowire surface plasmons, for possible experimental realization.

Show MeSH

Related in: MedlinePlus

The original LG inequality for as a function of time.The blue-dotted, dashed, and solid curves represent the results of the observables Q = Q1 = /1, 0〉 〈1, 0/, Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, and Q = Q3 = 1–2 /0, 1〉 〈0, 1/, respectively. In plotting this figure, the initial state is assumed to be /1, 0〉.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC3753592&req=5

f3: The original LG inequality for as a function of time.The blue-dotted, dashed, and solid curves represent the results of the observables Q = Q1 = /1, 0〉 〈1, 0/, Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, and Q = Q3 = 1–2 /0, 1〉 〈0, 1/, respectively. In plotting this figure, the initial state is assumed to be /1, 0〉.

Mentions: Normally, the LG inequality is applied to a macroscopic object to verify the property of macroscopic realism. Here, we wish to make use of it as a tool to check the quantumness (quantum coherent dynamics) during the superradiant process. By choosing t1 = t2 = t with the initial state being in /1, 0〉, we apply the original LG inequality in Eq. (12) to examine the quantumness in the two-emitter SR scenario. If we choose Q = Q1 = /1, 0〉 〈1, 0/ as our observable, there is no violation of LGQ(t) as shown by the blue-dotted curve in Fig. 3. This coincides with our intuition: the decay of the state /1, 0〉 is a monotonically decreasing function. However, if we choose Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, i.e. the excitation is not in the second emitter, the red-dashed curve shows the violation of in the early stage of the time domain. We also plot in Fig. 3 the result of Q = Q3 = 1–2 /0, 1〉 〈0, 1/. One can see that the maximum of the violation is enhanced. The analytical results of LQ(t) can also be worked out. For instance, the expression of is where .


Examining non-locality and quantum coherent dynamics induced by a common reservoir.

Chen GY, Chen SL, Li CM, Chen YN - Sci Rep (2013)

The original LG inequality for as a function of time.The blue-dotted, dashed, and solid curves represent the results of the observables Q = Q1 = /1, 0〉 〈1, 0/, Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, and Q = Q3 = 1–2 /0, 1〉 〈0, 1/, respectively. In plotting this figure, the initial state is assumed to be /1, 0〉.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3753592&req=5

f3: The original LG inequality for as a function of time.The blue-dotted, dashed, and solid curves represent the results of the observables Q = Q1 = /1, 0〉 〈1, 0/, Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, and Q = Q3 = 1–2 /0, 1〉 〈0, 1/, respectively. In plotting this figure, the initial state is assumed to be /1, 0〉.
Mentions: Normally, the LG inequality is applied to a macroscopic object to verify the property of macroscopic realism. Here, we wish to make use of it as a tool to check the quantumness (quantum coherent dynamics) during the superradiant process. By choosing t1 = t2 = t with the initial state being in /1, 0〉, we apply the original LG inequality in Eq. (12) to examine the quantumness in the two-emitter SR scenario. If we choose Q = Q1 = /1, 0〉 〈1, 0/ as our observable, there is no violation of LGQ(t) as shown by the blue-dotted curve in Fig. 3. This coincides with our intuition: the decay of the state /1, 0〉 is a monotonically decreasing function. However, if we choose Q = Q2 = /1, 0〉 〈1, 0/ + /0, 0〉 〈0, 0/, i.e. the excitation is not in the second emitter, the red-dashed curve shows the violation of in the early stage of the time domain. We also plot in Fig. 3 the result of Q = Q3 = 1–2 /0, 1〉 〈0, 1/. One can see that the maximum of the violation is enhanced. The analytical results of LQ(t) can also be worked out. For instance, the expression of is where .

Bottom Line: Here, we propose to use the steering inequality to examine the non-locality induced by a common reservoir.Compared with the Bell inequality, we find that the steering inequality has a better tolerance for examining non-locality.In view of the dynamic nature of the entangling process, we also propose to observe the quantum coherent dynamics by using the Leggett-Garg inequalities.

View Article: PubMed Central - PubMed

Affiliation: Department of Physics, National Chung Hsing University, Taichung 402, Taiwan.

ABSTRACT
If two identical emitters are coupled to a common reservoir, entanglement can be generated during the decay process. When using Bell's inequality to examine the non-locality, however, it is possible that the bound cannot be violated in some cases. Here, we propose to use the steering inequality to examine the non-locality induced by a common reservoir. Compared with the Bell inequality, we find that the steering inequality has a better tolerance for examining non-locality. In view of the dynamic nature of the entangling process, we also propose to observe the quantum coherent dynamics by using the Leggett-Garg inequalities. We also suggest a feasible scheme, which consists of two quantum dots coupled to nanowire surface plasmons, for possible experimental realization.

Show MeSH
Related in: MedlinePlus