How adsorption influences DNA denaturation (2009)
Allahverdyan, A. E., Gevorkian, Zh. S., Hu, Chin-Kun, Nieuwenhuizen, Th. M.
The thermally induced denaturation of DNA in the presence of attractive solid surface is studied. The two strands of DNA are modeled via two coupled flexible chains without volume interactions. If...
Post-adiabatic forces and Lagrangians with higher-order derivatives (2009)
Allahverdyan, A. E., Mehmani, B.
We study a slow classical system [particle] coupled to a fast quantum system with discrete energy spectrum. We adiabatically exclude the quantum system and construct an automous dynamics for the...
Kolmogorov cosmic microwave background sky (2008)
Gurzadyan, V. G., Allahverdyan, A. E., Ghahramanyan, T., Kashin, A. L., Khachatryan, H. G., Kocharyan, A. A., ...
A new map of the sky representing the degree of randomness in the cosmic microwave background (CMB) temperature has been obtained. The map based on estimation of the Kolmogorov stochasticity...
Thermodynamics of adiabatic feedback control (2008)
Allahverdyan, A. E., Saakian, D. B.
We study adaptive control of classical ergodic Hamiltonian systems, where the controlling parameter varies slowly in time and is influenced by system's state (feedback). An effective adiabatic...
Thermal (in)stability of type I collagen fibrils (2008)
Gevorkian, S. G., Allahverdyan, A. E., Gevorgyan, D. S., Simonian, A. L.
We measured Young's modulus at temperatures ranging from 20 to 100 ^{\circ}$C for a collagen fibril taken from rat's tendon. The hydration change under heating and the damping decrement were measured...
Quantum-state tomography using a single apparatus (2008)
Mehmani, B., Allahverdyan, A.E., Nieuwenhuizen, T.M.
The density matrix of a two-level system (spin, atom) is usually determined by measuring the three noncommuting components of the Pauli vector. This density matrix can also be obtained via the...
Quantum state tomography using a single apparatus (2007)
Mehmani, B., Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The density matrix of a two-level system (spin, atom) is usually determined by measuring the three non-commuting components of the Pauli vector. This density matrix can also be obtained via the...
Minimal Work Principle and its Limits for Classical Systems (2006)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The minimal work principle asserts that work done on a thermally isolated equilibrium system, is minimal for the slowest (adiabatic) realization of a given process. This principle, one of the...
Adiabatic feedback control of Hamiltonian systems (2006)
Allahverdyan, A. E., Petrosyan, K. G., Saakian, D. B.
We study feedback control of classical Hamiltonian systems with the controlling parameter varying slowly in time. The control aims to change system's energy. We show that the control problems can be...
Adhesion-induced DNA naturation (2006)
Allahverdyan, A.E., Gevorkian, Z.S., Hu, C.K., Nieuwenhuizen, T.M.
Adhesion Induced DNA Naturation (2005)
Allahverdyan, A. E., Gevorkian, Zh. S., Hu, Chin-Kun, Nieuwenhuizen, Th. M.
DNA adsorption and naturation is modeled via two interacting flexible homopolymers coupled to a solid surface. DNA denatures if the entropy gain for unbinding the two strands overcomes the loss of...
Anomalous latent heat in non-equilibrium phase transitions (2005)
Allahverdyan, A. E., Petrosyan, K. G.
We study first-order phase transitions in a two-temperature system, where due to the time-scale separation all the basic thermodynamical quantities (free energy, entropy, etc) are well-defined. The...
Statistical networks emerging from link-node interactions (2005)
Allahverdyan, A. E., Petrosyan, K. G.
We study a model for a statistical network formed by interactions between its nodes and links. Each node can be in one of two states (Ising spin up or down) and the node-link interaction facilitates...
Explanation of the Gibbs paradox within the framework of quantum thermodynamics (2005)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The issue of the Gibbs paradox is that when considering mixing of two gases within classical thermodynamics, the entropy of mixing appears to be a discontinuous function of the difference between the...
Allahverdyan, A. E., Khrennikov, A., Nieuwenhuizen, Th. M.
We show that for two classical brownian particles there exists an analog of continuous-variable quantum entanglement: The common probability distribution of the two coordinates and the corresponding...
Bath Assisted Cooling of Spins (2004)
Allahverdyan, A. E., Gracia, R. Serral, Nieuwenhuizen, Th. M.
A suitable sequence of sharp pulses applied to a spin coupled to a bosonic bath can cool its state, i.e., increase its polarization or ground state occupation probability. Starting from an...
Work extraction in the spin-boson model (2004)
Allahverdyan, A. E., Gracia, R. Serral, Nieuwenhuizen, Th. M.
We show that work can be extracted from a two-level system (spin) coupled to a bosonic thermal bath. This is possible due to different initial temperatures of the spin and the bath, both positive (no...
The second law and fluctuations of work: The case against quantum fluctuation theorems (2004)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
We study how Thomson's formulation of the second law: no work is extracted from an equilibrium ensemble by a cyclic process, emerges in the quantum situation through the averaging over fluctuations...
Minimal work principle: proof and counterexamples (2004)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The minimal work principle states that work done on a thermally isolated equilibrium system is minimal for adiabatically slow (reversible) realization of a given process. This principle, one of the...
Unzipping of DNA with correlated base-sequence (2004)
Allahverdyan, A. E., Gevorkian, Zh. S., Hu, Chin-Kun, Wu, Ming-Chya
We consider force-induced unzipping transition for a heterogeneous DNA model with a correlated base-sequence. Both finite-range and long-range correlated situations are considered. It is shown that...
Quantum thermodynamics: thermodynamics at the nanoscale (2004)
Allahverdyan, A. E., Balian, R., Nieuwenhuizen, Th. M.
A short introduction on quantum thermodynamics is given and three new topics are discussed: 1) Maximal work extraction from a finite quantum system. The thermodynamic prediction fails and a new,...
Maximal work extraction from quantum systems (2004)
Allahverdyan, A. E., Balian, R., Nieuwenhuizen, Th. M.
Thermodynamics teaches that if a system initially off-equilibrium is coupled to work sources, the maximum work that it may yield is governed by its energy and entropy. For finite systems this bound...
Adiabatic processes need not correspond to optimal work (2004)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The minimum work principle states that work done on a thermally isolated equilibrium system is minimal for the adiabatically slow (reversible) realization of a given process. This principle, one of...
Determining a quantum state by means of a single apparatus (2003)
Allahverdyan, A. E., Balian, R., Nieuwenhuizen, Th. M.
The unknown state $\hrho$ of a quantum system S is determined by letting it interact with an auxiliary system A, the initial state of which is known. A one-to-one mapping can thus be realized between...
The quantum measurement process: an exactly solvable model (2003)
Allahverdyan, A. E., Balian, R., Nieuwenhuizen, Th. M.
An exactly solvable model for a quantum measurement is discussed, that integrates quantum measurements with classical measurements. The z-component of a spin-1/2 test spin is measured with an...
Force-induced unzipping of DNA with long-range correlated sequence (2002)
Allahverdyan, A. E., Gevorkian, Zh. S.
We consider force-induced unzipping transition for a heterogeneous DNA model with a long-range correlated base-sequence. It is shown that as compared to the uncorrelated situation, long-range...
Arrows of Time and Chaotic Properties of the Cosmic Background Radiation (2002)
Allahverdyan, A. E., Gurzadyan, V. G.
We advance a new viewpoint on the connection between the the thermodynamical and cosmological arrows of time, which can be traced via the properties of Cosmic Microwave Background (CMB) radiation. We...
From Fermi-Pasta-Ulam Problem to Galaxies: The Quest for Relaxation (2002)
Allahverdyan, A. E., Gurzadyan, V. G.
The major problem posed by the Fermi-Pasta-Ulam work was the relaxation (thermalization) of a many-body system. We review two approaches to this problem, the ergodic theory and Langevin (stochastic)...
Invalidity of the Landauer inequality for information erasure in the quantum regime (2002)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
A known aspect of the Clausius inequality is that an equilibrium system subjected to a squeezing $\d S
On testing the violation of the Clausius inequality in nanoscale electric circuits (2002)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The Clausius inequality, one of the classical formulations of the second law, was recently found to be violated in the quantum regime. Here this result is formulated in the context of a mesoscopic or...
Bath generated work extraction and inversion-free gain in two-level systems (2002)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The spin-boson model, often used in NMR and ESR physics, quantum optics and spintronics, is considered in a solvable limit to model a spin one-half particle interacting with a bosonic thermal bath....
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
There are several formulations of the second law, and they may, in principle, have different domains of validity. Here a simple mathematical theorem is proven which serves as the most general basis...
Kinetic equation model for self-gravitating systems (2001)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The kinetic theory of a self-gravitating system is considered in the framework of Bhatnager-Gross-Krook model. This approach offers a unique and tractable setup for studying the central,...
Mean-field theory of quantum brownian motion (2001)
Allahverdyan, A. E., Balian, R., Nieuwenhuizen, Th. M.
We investigate a mean-field approach to a quantum brownian particle interacting with a quantum thermal bath at temperature $T$, and subjected to a non-linear potential. An exact, partially classical...
Breakdown of the Landauer bound for information erasure in the quantum regime (2000)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
A known aspect of the Clausius inequality is that an equilibrium system subjected to a squeezing $\d S$ of its entropy must release at least an amount $|\dbarrm Q|=T|\d S|$ of heat. This serves as a...
Nieuwenhuizen, Th. M., Allahverdyan, A. E.
The Brownian motion of a quantum particle in a harmonic confining potential and coupled to a harmonic quantum thermal bath is exactly solvable. It is shown that at low enough temperatures the...
Reply on Comment on ``Extraction of work from a single thermal bath in the quantum regime'' (2000)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
In our recent letter [1] we discussed that thermodynamics is violated in quantum Brownian motion beyond the weak coupling limit. In his comment, Tasaki [2] derives an inequality for the relative...
Extraction of work from a single thermal bath in the quantum regime (2000)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
The stationary state of a quantum particle strongly coupled to a quantum thermal bath is known to be non-gibbsian, due to entanglement with the bath. For harmonic potentials, where the system can be...
Optimizing the classical heat engine (2000)
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
A pair of systems at different temperatures is a classic environment for a heat engine, which produces work during the relaxation to a common equilibrium. It is generally believed that a direct...
On the Numerical Study of the Complexity and Fractal Dimension of CMB Anisotropies (1999)
Allahverdyan, A. E., Gurzadyan, V. G., Soghoyan, A. A.
We consider the problem of numerical computation of the Kolmogorov complexity and the fractal dimension of the anisotropy spots of Cosmic Microwave Background (CMB) radiation. Namely, we describe an...
Arrows of Time and the Anisotropic Properties of CMB (1999)
Allahverdyan, A. E., Gurzadyan, V. G.
The relation between the thermodynamical and cosmological arrows of time is usually viewed in the context of the initial conditions of the Universe. It is a necessary but not sufficient condition for...
Allahverdyan, A. E., Nieuwenhuizen, Th. M.
In a glassy system different degrees of freedom have well-separated characteristic times, and are described by different temperatures. The stationary state is essentially non-equilibrium. A...
Model glasses coupled to two different heat baths (1999)
Allahverdyan, A. E., Nieuwenhuizen, Th. M., Saakian, D. B.
In a $p$-spin interaction spherical spin-glass model both the spins and the couplings are allowed to change in the course of time. The spins are coupled to a heat bath with temperature $T$, while the...
About optimal measurements in quantum hypothesizes testing (1998)
Allahverdyan, A. E., Saakian, D. B.
We consider the problem of a state determination for a two-level quantum system which can be in one of two nonorthogonal mixed states. It is proved that for the two independent identical systems the...
Spin-glass model with partially annealed asymmetric bonds (1998)
Allahverdyan, A. E., Saakian, D. B.
We have considered the two-spin interaction spherical spin-glass model with asymmetric bonds (coupling constants). Besides the usual interactions between spins and bonds and between the spins and a...
Allahverdyan, A. E., Saakian, D. B.
A strengthened Lindblad inequality has been proved. We have applied this result for proving a generalized $H$-theorem in non equilibrium thermodynamics. Information processing also can be considered...
The broadcast quantum channel for classical information transmission (1998)
Allahverdyan, A. E., Saakian, D. B.
It is well known that quantum theory forbids the exact copying of an unknown quantum state. Therefore in broadcasting of classical information by a quantum channel an additional contribution to the...
Multi-access channels in quantum information theory (1997)
Allahverdyan, A. E., Saakian, D. B.
The multi-access channels in quantum information theory are considered. Classical messages from independent sources, which are represented as some quantum states, are transported by a channel to one...
Data processing in quantum information theory (1997)
Allahverdyan, A. E., Saakian, D. B.
The strengthened data processing inequality have been proved. The general theory have been illustrated on the simple example.
Converse coding theorems for quantums source and noisy channel (1997)
Allahverdyan, A. E., Saakian, D. B.
The weak converse coding theorems have been proved for the quantum source and channel. The results give the lower bound for capacity of source and the upper bound for capacity of channel. The...