Quantum Statistics of Light Emitted from a Pillar Microcavity

A quantum behavior of the light emitted by exciton polaritons excited in a pillar semiconductor microcavity with embedded quantum well is investigated. Considering the bare excitons and photon modes as coupled quantum oscillators allows for an accurate accounting of the nonlinear and dissipative effects. In particular, using the method of quantum states presentation in a quantum phase space via quasiprobability functions (namely, a P-function and a Wigner function), we study the effect of the laser and the exciton-photon detuning on the second order correlation function of the emitted photons. We determine the conditions for the phenomena of bunching, giant bunching, and antibunching of the emitted light. In particular, we predict the effect of a giant bunching for the case of a large exciton to photon population ratio. Within the domain of parameters supporting a bistability regime we demonstrate the effect of bunching of photons.

Celebrating the 100th Anniversary of Ferroelectricity

It is 100 years when we think about the history of ferroelectricity. We, who study ferroelectricity, are honored and pleased to share the 100-year anniversary of ferroelectricity and recall its history. At this great moment, we look back to the brief history on the verge of ferroelectricity. Our hope is that ferroelectricity studied as an early collective phenomenon will be coupled with quantum behavior, the essence of modern science, to become a new age in the history of science and technology.

Unitary Structure of Palindromes in DNA

We investigate the quantum behavior encountered in palindromes within DNA structure. In particular we reveal the unitary structure of usual palindromic sequences found in genomic DNAs of all living organisms using the Schwinger approach. We clearly demonstrate the role played by palindromic configurations with special emphasis on physical symmetries in particular subsymmetries of unitary structure. We unveil the prominence of unitary structure in palindromic sequences in the sense that vitally significant information endowed within DNA could be transformed unchangeably in the process of transcription. We introduce a new symmetry relation namely purine-purine or pyrimidine-pyrimidine symmetries (p-symmetry) in addition to the already known symmetry relation of purine-pyrimidine symmetries (pp symmetry) given by Chargaff rule. Therefore important vital functions of a living organisms are protected by means of these symmetric features. It is understood that higher order palindromic sequences could be generated in terms of the basis of the highest prime numbers that make up the palindrome sequence number. We propose that violation of this unitary structure of palindromic sequences by means of our proposed symmetries leads to a mutation in DNA which could offer a new perspective in the scientific studies on the origin and cause of mutation.

Loss and Dissipation: The RLC Circuit

The effects of energy loss or dissipation is well-known and understood in classical systems. It is the source of heat in LCR circuits and in the application of brakes in a vehicle or why a struck bell does not ring indefinitely. Understanding quantum behavior begins with understanding the Hamiltonian for the problem. Classically, loss arises from a coupling of the Hamiltonian for an isolated quantum system to a continuum of states. We look at such a Hamiltonian and develop the equations of motion following the rules of quantum mechanics and find that even in a quantum system, this coupling leads to loss and non-conservation of probability in the otherwise isolated quantum system. This is the Weisskopf–Wigner formalism that is then used to understand the quantum LCR circuit. The same formalism is used in Chapter 15 for the decay of isolated quantum systems by coupling to the quantum vacuum and the resulting emission of a photon.