Nonlinear spectrum effect on the coherent control of molecular systems

This work demonstrates that the detuning of the fs-laser spectrum from the two-photon absorption band of organic materials can be used to reach further control of the two-photon absorption by pulse spectral phase manipulation. We investigate the coherent control of the two-photon absorption in imidazole-thiophene core compounds presenting distinct two-photon absorption spectra. The coherent control, performed using pulse phase shaping and genetic algorithm, exhibited different growth rates for each sample. Such distinct trends were explained by calculating the two-photon absorption probability considering the intrapulse interference mechanism, taking into account the two-photon absorption spectrum of the samples. Our results indicate that tuning the relative position between the nonlinear absorption and the pulse spectrum can be used as a novel strategy to optimize the two-photon absorption in broadband molecular systems. (C) 2011 Elsevier B.V. All rights reserved.

A utilitarian argument: laying the foundation for a coherent system of law

Even the most ardent legal positivists agree that as a matter offact there is a connection between law and morality. In most Western legal systems this association is very strong. Underpinning most legal rules is a (real or  purported) moral principle - certainly it is difficult to find examples of laws which are clearly immoral. The foundation upon which a coherent and justifiable legal system must be built is a theory of morality.

Legal ethics is (just) normal ethics: towards a coherent system of legal ethics

The standards governing how lawyers ought to conduct themselves consist of a number disparate principles and rules, which are devoid of an overarching rationale. We argue that legal ethics is not a stand-alone social construct. Rather, it is the application of normal ethical principles so far as they relate to the law. Approached in this manner, legal ethics becomes a far more coherent and justifiable institution. In this paper we apply general moral theory to several key dilemmas facing lawyers. This results in outcomes which some may find counter-intuitive. We conclude that lawyers should not do pro bono work; that the first cab rank off the rank principle is unsound and that there is no relevant difference between expressly misleading the court and putting the other side to the proof of its case.

What's instinct got to do with it? A blueprint for a coherent approach to punishing criminals

As a result of the instinctive synthesis approach to sentencing, decisions are often based on the intuitive inclinations and sentiments of sentencers, as opposed to binding rules and principles. In particular, insufficient regard is paid to the purposes and objectives that can be achieved through a state-imposed system of punishment. Momentum is gathering for the High Court to revisit the manner in which the sentencing inquiry is undertaken. We believe that the court should use the opportunity to implement fundamental reform in sentencing and direct the sentencing process down a more transparent and forensic path. We suggest that there are seven basic steps that need to be undertaken to achieve enlightened sentencing reform. Ideally this is a role for the legislature. However, given the populist climate in which we live we have little confidence that the legislature will undertake such an exacting task – one which would almost certainly lead to a less severe sentencing regime. The judiciary offers the strongest hope that at least some of these steps will be taken. This article offers a blueprint for how such reform can be implemented. The first step is simply to assume that the institution of state-imposed punishment is justified – this has already been undertaken. The second is to select the theory which best justifies punishing wrongdoers. Thirdly, public opinion must be ignored in developing sentencing principle. Next it must be determined which objectives (such as deterrence and rehabilitation) can be achieved through sentencing. The fifth step involves matching the punishment to the crime. Step six is to critically analyse the foundation, and reassess the relevance, of the hundreds of aggravating and mitigating considerations that presently affect the sentencing calculus. Finally, sentencing law and practice should be subject to ongoing reform to take into account emerging empirical evidence concerning the positive benefits that can be achieved through sentencing.

International sentencing law: in search of a justification and coherent framework

An international sentencing jurisprudence is emerging from the decisions by the International Criminal Tribunal for the Former Yugoslavia (ICTY or the Yugoslav tribunal) and the International Criminal Tribunal for Rwanda (ICTR or the Rwanda tribunal) (collectively, 'the tribunals'). This article examines international sentencing law and practice and discusses the justification for the practice. International sentencing law has several objectives. The main goals are reconciliation, deterrence, retribution and rehabilitation. The sentencing inquiry is marked by a high degree of discretion and has resulted in sentencers developing a large amount of aggravating and mitigating considerations, such as being in a position of authority, remorse and good character. It is argued that the current international sentencing approach is flawed - fundamentally so. Most of the stated goals of international sentencing in the form of reconciliation, retribution and rehabilitation are either highly speculative or misguided. The only justification for the practice is general deterrence. This is, however, significantly undermined by the selective and infrequent enforcement of crimes within the jurisdiction of such tribunals. The stated aggravated and mitigating considerations are not valid given that they are not justified by reference to the stated aims of sentencing and only serve to undermine the search for a penalty which is commensurate the serious of the offence. This article suggests a coherent framework for international sentencing policy and practice.

In search of coherent jurisprudence for international criminal law : correlating universal human responsibilities with universal human rights

I. The Evolution of International Criminal Law International criminal justice concerns breaches of international rules entailing the personal criminal liability of individuals (as opposed to the State for which the individuals may act as agents or organs), and presently includes acts such as genocide, torture, crimes against humanity, aggression and terrorism. ... A rule stating: any act of armed conflict which directly causes the death of a civilian is a war crime unless it can be shown that the military advantage gained by the attack outweighs the harm. ... Thus, so far as international criminal law is concerned any act during armed conflict which results in the death or injury to a person who does not pose a direct threat to the life of the accused should be a war crime. ... Pursuant to the Rome Statute and as a matter of customary international law torture is a war crime when performed in the context of an armed conflict, and a crime against humanity when it is part of systematic criminal conduct. ... Torture can also constitute an individual international crime, even where it does not satisfy the criteria of a war crime or crime against humanity. ...

Incremental learning of temporally-coherent gaussian mixture models

In this paper we address the problem of learning Gaussian Mixture Models (GMMs) incrementally. Unlike previous approaches which universally assume that new data comes in blocks representable by GMMs which are then merged with the current model estimate, our method works for the case when novel data points arrive oneby- one, while requiring little additional memory. We keep only two GMMs in the memory and no historical data. The current fit is updated with the assumption that the number of components is fixed, which is increased (or reduced) when enough evidence for a new component is seen. This is deduced from the change from the oldest fit of the same complexity, termed the Historical GMM, the concept of which is central to our method. The performance of the proposed method is demonstrated qualitatively and quantitatively on several synthetic data sets and video sequences of faces acquired in realistic imaging conditions

Incremental learning of temporally-coherent Gaussian mixture models

In this paper we address the problem of learning Gaussian Mixture Models (GMMs) incrementally. Unlike previous approaches which universally assume that new data comes in blocks representable by GMMs which are then merged with the current model estimate, our method works for the case when novel data points arrive one- by-one, while requiring little additional memory. We keep only two GMMs in the memory and no historical data. The current fit is updated with the assumption that the number of components is fixed which is increased (or reduced) when enough evidence for a new component is seen. This is deducedfrom the change from the oldest fit of the same complexity, termed the Historical GMM, the concept of which is central to our method. The performance of the proposed method is demonstrated qualitatively and quantitatively on several synthetic data sets and video sequences of faces acquired in realistic imaging conditions.

Two-colour photocurrent detection technique for coherent control of a single InGaAs/GaAs quantum dot

We present a two-colour photocurrent detection method for coherent control of a single InGaAs/GaAs self-assembled quantum dot. A pulse shaping technique provides a high degree of control over picosecond optical pulses. Rabi rotations on the exciton to biexciton transition are presented, and fine structure beating is detected via time-resolved measurements. (c) 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

Towards coherent optical control of a single hole spin: Rabi rotation of a trion conditional on the spin state of the hole

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Coherent properties and Rabi oscillations in two-level donor systems

Coherent properties and Rabi oscillations in two-level donor systems, under terahertz excitation, are theoretically investigated. Here we are concerned with donor states in bulk GaAs and GaAs-(Ga,Al)As quantum dots. We study confinement effects, in the presence of an applied magnetic field, on the electronic and on-center donor states in GaAs- (Ga,Al)As dots, as compared to the situation in bulk GaAs, and estimate some of the associated decay rate parameters. Using the optical Bloch equations with damping, we study the time evolution of the Is and 2p(+) states in the presence of an applied magnetic field and of a terahertz laser. We also discuss the role played by the distinct dephasing rates on the photocurrent and calculate the electric dipole transition moment. Results indicate that the Rabi oscillations are more robust as the total dephasing rate diminishes, corresponding to a favorable coherence time.

Asymptotics for Gegenbauer-Sobolev orthogonal polynomials associated with non-coherent pairs of measures

Inner products of the type < f, g >(S) = < f, g >psi(0) + < f', g'>psi(1), where one of the measures psi(0) or psi(1) is the measure associated with the Gegenbauer polynomials, are usually referred to as Gegenbauer-Sobolev inner products. This paper deals with some asymptotic relations for the orthogonal polynomials with respect to a class of Gegenbauer-Sobolev inner products. The inner products are such that the associated pairs of symmetric measures (psi(0), psi(1)) are not within the concept of symmetrically coherent pairs of measures.

Zeros of Gegenbauer-Sobolev Orthogonal Polynomials: Beyond Coherent Pairs

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Asymptotics for Jacobi-Sobolev orthogonal polynomials associated with non-coherent pairs of measures

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)