Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Canadian Journal of Physics

Sub-Poissonian photon statistics of light in interaction of two-level atoms in superposed states with a single mode superposed coherent radiation

Rakesh Kumar Rai, Hari Prakash

Published Mar 1, 2010• 6 citations
Publisher

Abstract

We study sub-Poissonian photon statistics of light in interaction of a single mode radiation, initially either in a coherent state or in a superposed coherent state with an assembly of two-level atoms using the Hamiltonian, H = ω(a+a + Sz) + g(aS+ + a+ S–) in natural units, where a+ and a are creation and annihilation operators, Sz, S ± are the collective Dicke operators, g is the coupling constant, and ω is the energy of the photons and also the separation between the two atomic levels. We study the cases of (i) a single two-level and (ii) of two two-level atoms interacting with a single mode coherent or superposed coherent radiation. We find that for large coupling time gt, Fano factor shows collapses and revival phenomena, and that the variation is large for small mean number of photons. We also find that in the case of two two-level atoms, photon statistics shows larger sub-Poissonian than the case of a single two-level atom, and that there is no definite relationship between squeezing and sub-Poissonian photon statistics of light.

DOI
10.1139/p09-115

Related papers

Higher-Order Sub-Poissonian statistics in interaction of two two-level atoms with a single mode coherent radiation

Rakesh Kumar

In the present paper we study higher-order sub-Poissonian photon statistics in interaction of a single mode radiation initially in the coherent state Ŧα〉 with an assembly of two excited two-level atoms using the Hamiltonian, H=ω(a+a+Sz)+g(aS++a+S.), in the natural system of units. Here, α=|α|eiθα, a is the annihilation operator for radiation, Sz and S± are the collective Dicke operators, g is the coupling constant, ω is the energy of the photons and the energy difference between the two atomic levels. We solve it exactly and conclude that higher-order sub-Poissonian photon statistics can be obtained for an arbitrary order by choosing suitably the square root of mean photon number |α| of the coherent radiation and coupling time gt. Variations of higher-order sub-Poissonian photon statistics with parameters |α| and gt have also been discussed.

Indian Journal of Scientific Research•Jan 1, 2015•0 citations

ORDINARY SQUEEZING AND AMPLITUDE-SQUARED SQUEEZING OF A SINGLE MODE COHERENT RADIATION IN INTERACTION WITH TWO TWO-LEVEL ATOMS

Hari Prakash, Rakesh Kumar Rai

In the present paper, we consider the interaction of a single mode radiation initially in a coherent state with an assembly of two two-level atoms in some different states using the Hamiltonian, H = ω(a+a + Sz)+g(a S+ + a+ S-) in the natural units, where a+ and a are the creation and annihilation operators for radiation, Sz, S± are the collective Dicke operators, g is the coupling constant, ω is the energy of the photons and energy difference between the two atomic levels. We solve it exactly. We study ordinary squeezing and amplitude-squared squeezing of radiation for the general operators, [Formula: see text] and Yθ=1/2(a2e-iθ+a+2eiθ), when atoms are fully excited, super-radiant or in the ground state. We get a large ordinary squeezing (nearly 88% squeezing) for the super-radiant atomic state, at a time, which is 0.451 of the first revival time, and this should be easily observable. We also get a large amplitude-squared squeezing (nearly 20%) at the time, which is about 0.033 of the first revival time. Variation of variances near their minima with coupling time gt, square root of mean photon number |α| and phase are also discussed.

International Journal of Modern Physics B•Aug 10, 2007•10 citations

Bounds on sub-Poissonian field statistics in the Jaynes-Cummings model

Mark S. Hillery

The Jaynes-Cummings model describes the interaction between a two-level atom and a single mode of the radiation field. This system has a conservation law which restricts its dynamics. On the basis of this conservation law alone one can make useful statements about the photon statistics of the fields which arise in the model. Two cases are considered. In the first the field is initially in a coherent state. Here it is found that the field statistics become less sub-Poissonian as the amplitude of the initial state increases. The case of an initial thermal state is also considered. In that situation, if the average number of photons present in the initial state is greater than 2.55, then the field statistics can never become sub-Poissonian.

Physical Review A•May 1, 1987•29 citations

Sub-Poissonian radiation of a one-atom two-level laser with incoherent pumping

A. V. Kozlovskiĭ, А. Н. Ораевский

The quantum statistical properties of the radiation of a one-atom two-level laser with incoherent pumping are analyzed. Solution of the Liouville equation for the density operator in the basis of Fock states shows that stationary radiation from a single-mode laser with incoherent pumping can be in a squeezed (sub-Poissonian) stationary state if the rate of spontaneous decay is lower than the rate of cavity losses and the pump rate. Inside the cavity the Fano factor reaches F =0.85 (15% squeezing). Multiple squeezing ( F =0.19) is possible in the transient lasing regime. Significant squeezing obtains at the cavity output; the spectral Fano factor at zero frequency is 0.36 under optimal conditions.

Journal of Experimental and Theoretical Physics•Apr 1, 1999•12 citations

COLLAPSES AND REVIVALS IN TWO-LEVEL ATOMS IN A SUPERPOSED STATE INTERACTING WITH A SINGLE MODE SUPERPOSED COHERENT RADIATION

Hari Prakash, Rakesh Kumar Rai

Collapses and revivals phenomenon in system of a single two-level atom and two two-level atoms existing in some superposed states and interacting with a single mode superposed coherent radiation is studied. For superposed Dicke states |1/2, ±1/2> of a single two-level atom interacting with even or odd coherent state, only odd revivals occur. For two two-level atoms, it is found that the collapse and revival times for even and odd coherent states are equal to one half of the corresponding times for coherent state. For this system, Rabi oscillations occur with a main mean frequency and also some second harmonics are present, in general. However, if the two atoms are in the superradiant state, only the second harmonics with large amplitude are obtained. The appearance of weak double frequency revivals for superposed atomic and coherent states was studied and a condition for their disappearance is found.

International Journal of Modern Physics B•Jul 10, 2008•4 citations

Bounds from a conservation law in the Dicke model

Mark S. Hillery, Leonard D. Mlodinow

We study N two-level atoms coupled to a single mode of the electromagnetic field. This system obeys a conservation law that restricts the set of states which can be reached by time evolution from a given initial state. This fact allows one to calculate time-independent bounds for certain observables, in particular, the uncertainty in photon number, \ensuremath{\Delta}n. These bounds can be used to determine how sub- or super-Poissonian the photon statistics can become. This is done for an initial coherent state and an initial thermal state. For the coherent state the number of atoms must be greater than the square root of the initial number of photons for highly sub-Poissonian fields to be possible. On the other hand, for the thermal state N must be greater than the initial photon number for this to occur. In the case of the thermal state, we also find that the field will never become sub-Poissonian if the ratio of the initial photon number to N is greater than a quantity of order 1.

Physical Review A•Oct 1, 1988•0 citations
We study sub-Poissonian photon statistics of light in interaction of a single mode radiation, initially either in a coherent state or in a superposed coherent state with an assembly of two-level atoms using the Hamiltonian, H = ω(a+a + Sz) + g(aS+ + a+ S–) in natural units, where a+ and a are creation and annihilation operators, Sz, S ± are the collective Dicke operators, g is the coupling constant, and ω is the energy of the photons and also the separation between the two atomic levels. We study the cases of (i) a single two-level and (ii) of two two-level atoms interacting with a single mode coherent or superposed coherent radiation. We find that for large coupling time gt, Fano factor shows collapses and revival phenomena, and that the variation is large for small mean number of photons. We also find that in the case of two two-level atoms, photon statistics shows larger sub-Poissonian than the case of a single two-level atom, and that there is no definite relationship between squeezing and sub-Poissonian photon statistics of light.
In the present paper we study higher-order sub-Poissonian photon statistics in interaction of a single mode radiation initially in the coherent state Ŧα〉 with an assembly of two excited two-level atoms using the Hamiltonian, H=ω(a+a+Sz)+g(aS++a+S.), in the natural system of units. Here, α=|α|eiθα, a is the annihilation operator for radiation, Sz and S± are the collective Dicke operators, g is the coupling constant, ω is the energy of the photons and the energy difference between the two atomic levels. We solve it exactly and conclude that higher-order sub-Poissonian photon statistics can be obtained for an arbitrary order by choosing suitably the square root of mean photon number |α| of the coherent radiation and coupling time gt. Variations of higher-order sub-Poissonian photon statistics with parameters |α| and gt have also been discussed.
In the present paper, we consider the interaction of a single mode radiation initially in a coherent state with an assembly of two two-level atoms in some different states using the Hamiltonian, H = ω(a+a + Sz)+g(a S+ + a+ S-) in the natural units, where a+ and a are the creation and annihilation operators for radiation, Sz, S± are the collective Dicke operators, g is the coupling constant, ω is the energy of the photons and energy difference between the two atomic levels. We solve it exactly. We study ordinary squeezing and amplitude-squared squeezing of radiation for the general operators, [Formula: see text] and Yθ=1/2(a2e-iθ+a+2eiθ), when atoms are fully excited, super-radiant or in the ground state. We get a large ordinary squeezing (nearly 88% squeezing) for the super-radiant atomic state, at a time, which is 0.451 of the first revival time, and this should be easily observable. We also get a large amplitude-squared squeezing (nearly 20%) at the time, which is about 0.033 of the first revival time. Variation of variances near their minima with coupling time gt, square root of mean photon number |α| and phase are also discussed.
The Jaynes-Cummings model describes the interaction between a two-level atom and a single mode of the radiation field. This system has a conservation law which restricts its dynamics. On the basis of this conservation law alone one can make useful statements about the photon statistics of the fields which arise in the model. Two cases are considered. In the first the field is initially in a coherent state. Here it is found that the field statistics become less sub-Poissonian as the amplitude of the initial state increases. The case of an initial thermal state is also considered. In that situation, if the average number of photons present in the initial state is greater than 2.55, then the field statistics can never become sub-Poissonian.
The quantum statistical properties of the radiation of a one-atom two-level laser with incoherent pumping are analyzed. Solution of the Liouville equation for the density operator in the basis of Fock states shows that stationary radiation from a single-mode laser with incoherent pumping can be in a squeezed (sub-Poissonian) stationary state if the rate of spontaneous decay is lower than the rate of cavity losses and the pump rate. Inside the cavity the Fano factor reaches F =0.85 (15% squeezing). Multiple squeezing ( F =0.19) is possible in the transient lasing regime. Significant squeezing obtains at the cavity output; the spectral Fano factor at zero frequency is 0.36 under optimal conditions.
Collapses and revivals phenomenon in system of a single two-level atom and two two-level atoms existing in some superposed states and interacting with a single mode superposed coherent radiation is studied. For superposed Dicke states |1/2, ±1/2> of a single two-level atom interacting with even or odd coherent state, only odd revivals occur. For two two-level atoms, it is found that the collapse and revival times for even and odd coherent states are equal to one half of the corresponding times for coherent state. For this system, Rabi oscillations occur with a main mean frequency and also some second harmonics are present, in general. However, if the two atoms are in the superradiant state, only the second harmonics with large amplitude are obtained. The appearance of weak double frequency revivals for superposed atomic and coherent states was studied and a condition for their disappearance is found.
We study N two-level atoms coupled to a single mode of the electromagnetic field. This system obeys a conservation law that restricts the set of states which can be reached by time evolution from a given initial state. This fact allows one to calculate time-independent bounds for certain observables, in particular, the uncertainty in photon number, \ensuremath{\Delta}n. These bounds can be used to determine how sub- or super-Poissonian the photon statistics can become. This is done for an initial coherent state and an initial thermal state. For the coherent state the number of atoms must be greater than the square root of the initial number of photons for highly sub-Poissonian fields to be possible. On the other hand, for the thermal state N must be greater than the initial photon number for this to occur. In the case of the thermal state, we also find that the field will never become sub-Poissonian if the ratio of the initial photon number to N is greater than a quantity of order 1.