Professional Reputation, Cash, and Transition to Entrepreneurial Activity.

Cash; professional reputation; entrepreneurship;

Reputation Capital, Financial Capital, and Transition to Entrepreneurship.

We provide a theory for career choices of employees willing to become entrepreneurs and facing credit constraints. We show that they need a sufficient mix of reputation and financial capital. We consider their choice to work for transparent or opaque firms. Transparent firms disclose more information about their employees. It has two consequences. First, it eases the updating of the employees'reputation, which is positive for those with a bad initial reputation and negative otherwise. Second, it fosters incentives to exert effort, which increases the wage, and thus, the financial capital available for setting a business venture. Employees thus adopt strategies that depend on their initial reputation. We also show that employees whose alternative is to choose between transparent and opaque projects to work on once employed make transparency choices that differ from employees who choose firms to work for. The former are less likely to become entrepreneurs than the latter.Transition; Financial Capital; Career Concerns; Entrepreneurship; Reputation;

Access to financing, rents, and organization of the firm

This paper provides a theory for the choice of an organizational structure by the headquarters of a unitary structure concerned about overload. The headquarters can avoid overload by delegating operational decisions to divisions, i.e., moving the firm to a multidivisional structure. We show that, under moral hazard, these divisions receive rents for incentive purposes, and that the multidivisional structure is able to invest more. Thus, there is a trade-off between increasing investment and paying rents. We also show that this trade-off applies to situations where firms consider engaging in acquisitions and joint ventures, or where entrepreneurs consider resorting to venture capitalists.Unitary-form; Multidivisional-form; Agency rents; Credit rationing

When Promotions Induce Good Managers to Be Lazy

This paper shows that when being perceived as a good manager is a necessary condition to be promoted, a priori talented managers may undertake excessively risky projects. Indeed, such a choice renders more difficult the updating of beliefs process regarding their actual types. In turn, good managers are induced to lower the level of effort they perform since the extent to which effort impacts the perception the market has about their talent is lessened. This adversely impacts the firms' profits. Hence, career concerns do not discipline good managers in our context. However, we show how employers can limit managerial slack by increasing monitoringPromotions, career concerns, choice of risk, monitoring by corporate owners

Professional Reputation, Cash, and Transition to Entrepreneurial Activity.

We analyze the role of professional reputation in the transition to entrepreneurial activity when credit is rationed. We study an employee's willingness to allow the market to learn information about talent by choosing more or less informative projects. This choice impacts the employee's incentives to exert effort, which determines the wage, and in turn the cash to be invested in the business venture. We show that reputation and cash are substitutes in overcoming credit rationing. However, maintaining a good reputation conflicts with accumulating cash. Hence, employees adopt a different strategy depending on their initial reputation. Besides, starting a business venture early can in expectation be easier than waiting in order to build a reputation and accumulate cash.Corporate finance; Econométrie; Professional reputation; entrepreneurship;

Spin and recombination dynamics of excitons and free electrons in p-type GaAs : effect of carrier density

Carrier and spin recombination are investigated in p-type GaAs of acceptor concentration NA = 1.5 x 10^(17) cm^(-3) using time-resolved photoluminescence spectroscopy at 15 K. At low pho- tocarrier concentration, acceptors are mostly neutral and photoelectrons can either recombine with holes bound to acceptors (e-A0 line) or form excitons which are mostly trapped on neutral acceptors forming the (A0X) complex. It is found that the spin lifetime is shorter for electrons that recombine through the e-A0 transition due to spin relaxation generated by the exchange scattering of free electrons with either trapped or free holes, whereas spin flip processes are less likely to occur once the electron forms with a free hole an exciton bound to a neutral acceptor. An increase of exci- tation power induces a cross-over to a regime where the bimolecular band-to-band (b-b) emission becomes more favorable due to screening of the electron-hole Coulomb interaction and ionization of excitonic complexes and free excitons. Then, the formation of excitons is no longer possible, the carrier recombination lifetime increases and the spin lifetime is found to decrease dramatically with concentration due to fast spin relaxation with free photoholes. In this high density regime, both the electrons that recombine through the e-A0 transition and through the b-b transition have the same spin relaxation time.Comment: 4 pages, 5 figure

Spectrally narrow exciton luminescence from monolayer MoS2 exfoliated onto epitaxially grown hexagonal BN

The strong light-matter interaction in transition Metal dichalcogenides (TMDs) monolayers (MLs) is governed by robust excitons. Important progress has been made to control the dielectric environment surrounding the MLs, especially through hexagonal boron nitride (hBN) encapsulation, which drastically reduces the inhomogeneous contribution to the exciton linewidth. Most studies use exfoliated hBN from high quality flakes grown under high pressure. In this work, we show that hBN grown by molecular beam epitaxy (MBE) over a large surface area substrate has a similarly positive impact on the optical emission from TMD MLs. We deposit MoS$_2$ and MoSe$_2$ MLs on ultrathin hBN films (few MLs thick) grown on Ni/MgO(111) by MBE. Then we cover them with exfoliated hBN to finally obtain an encapsulated sample : exfoliated hBN/TMD ML/MBE hBN. We observe an improved optical quality of our samples compared to TMD MLs exfoliated directly on SiO$_2$ substrates. Our results suggest that hBN grown by MBE could be used as a flat and charge free substrate for fabricating TMD-based heterostructures on a larger scale.Comment: 5 pages, 3 figure

Electron spin quantum beats in positively charged quantum dots: nuclear field effects

We have studied the electron spin coherence in an ensemble of positively charged InAs/GaAs quantum dots. In a transverse magnetic field, we show that two main contributions must be taken into account to explain the damping of the circular polarization oscillations. The first one is due to the nuclear field fluctuations from dot to dot experienced by the electron spin. The second one is due to the dispersion of the transverse electron Lande g-factor, due to the inherent inhomogeneity of the system, and leads to a field dependent contribution to the damping. We have developed a model taking into account both contributions, which is in good agreement with the experimental data. This enables us to extract the pure contribution to dephasing due to the nuclei.Comment: 10 pages, 6 figure

Relations entre les entreprises et la recherche publique : lever des obstacles à l\u27innovation en France (Les)

Des relations étroites entre les entreprises qui opèrent près des deux tiers de la R&D française et les établissements publics de recherche constituent un moteur puissant en matière d’innovation. Néanmoins, malgré différentes actions de l’État en ce sens, elles apparaissent moins intenses en France que dans nombre de grands pays industriels. En s’appuyant sur la perception et les attentes d’un échantillon d’entreprises nationales ainsi que l’analyse de politiques publiques et d’outils développés en matière de recherche partenariale par des acteurs étrangers, une série de propositions visant à accroître et améliorer ces relations essentielles est présentée. Elle concerne le pilotage étatique des politiques publiques liées à l’innovation ainsi que les dispositifs incitatifs associés, le pilotage des politiques locales des établissements publics et des structures dédiées à la recherche partenariale, des mesures et dispositifs destinés à développer la mise en relation, accélérer la mise en oeuvre des partenariats et mobiliser les ressources humaines nécessaires