This document describes some of the research accomplishments of Prof. Boyd.

1. Foundations and Applications of Local Field Effects in Nonlinear Optics

Prof. Boyd and his coworkers have performed fundamental studies of the nature of local field effects in dense optical materials, and have shown that local field effects can be exploited to synthesize engineered materials with specially tailored nonlinear optical properties.

This work commenced with a laboratory study of local field effects in a dense atomic vapor. The influence of local field effects was controlled in this experiment by continuously varying the atomic number density. A key result of this project was the first measurement (Maki et al., 1991) of the Lorentz red shift, a shift of the atomic absorption line as a consequence of local field effects. This red shift had been predicted by Lorentz in the latter part of the nineteenth century, but had never previously been observed experimentally. In addition to confirming this century-old prediction, Boyd’s work is significant in confirming the validity of the Lorentz local-field formalism even under conditions associated with the resonance response of atomic vapors.

More recently, Boyd and coworkers have used local field effects to tailor the nonlinear optical response of composite optical materials. This work includes the prediction (Sipe and Boyd, 1992) and subsequent laboratory confirmation (Fischer et al., 1995) that it is possible to construct a composite material in such a manner that the nonlinear susceptibility of the composite exceeds those of the materials from which it is constructed. A three-fold enhancement of the nonlinear susceptibility has been demonstrated by this technique (Nelson and Boyd, 1999).

2. Optical Studies of Chaos and Nonlinear Dynamics

Prof. Boyd was an early leader in the field of optical chaos and nonlinear dynamics (Boyd et al., 1986). His team performed the first laboratory demonstrations of chaotic behavior in purely passive, resonatorless nonlinear optical systems. This work was crucial in elucidating the conditions under which an optical system could become unstable to chaotic behavior; prior to that time optical chaos had been observed only in lasers and in passive nonlinear optical systems in the presence of external feedback. This work entailed the observation of chaotic behavior in a photorefractive phase conjugate mirror (Gauthier et al., 1987) and the prediction (Gaeta et al., 1987) and subsequent observation (Gauthier et al., 1988) of chaotic behavior in the polarizations of counterpropagating laser beams in an atomic sodium vapor.

3. Fundamental Studies in Quantum and Nonlinear Optics and in Optical Phase Conjugation

Prof. Boyd has led a successful experimental effort (Malcuit et al., 1987) aimed at elucidating the relationship between superfluorescence and amplified spontaneous emission (ASE). The idea of this experiment was to fabricate a gain medium (monovalent molecular oxygen doped into single-crystal potassium chloride) for which the dipole dephasing rate could be controlled by varying the temperature of the sample. These workers found that at low temperatures the emission occurred through the process of superfluorescence, that is, the emission took place in the form of a well-defined pulse occurring after a short time delay. At higher temperatures, the emission occurred as a result of ASE, and the emission was in the form of a longer, noisy pulse with no time delay. The experiment also showed how the nature of the emission changed as the dephasing rate was varied continuously between the two limiting values. These results led to some excitement in the theoretical community as attempts were made to model the experimental results (Rzazewski, 1989; Maki et al., 1989).

Prof. Boyd has also performed fundamental studies in the field of nonlinear optics, including demonstrations of the role of Rabi oscillations in determining the nature of forward four-wave mixing processing in strongly driven atomic vapors (Harter et al., 1981), the role of atomic Rydberg states in leading to resonantly enhanced ultraviolet generation (Gauthier et al., 1983), and the ability of one nonlinear optical process to suppress another by means of quantum interference effects (Malcuit et al., 1985).

In the area of optical phase conjugation, Prof. Boyd has performed pioneering studies of the role of quantum noise in phase conjugation (Gaeta and Boyd, 1988), of the polarization properties of the phase conjugation process (Malcuit et al., 1988), of the process of Brillouin-enhanced four-wave mixing (Skeldon et al., 1987), of phase conjugate interferometry (Gauthier et al., 1989), of techniques for single-pass aberration correction (MacDonald et al., 1988), and of the design of phase conjugate laser systems (Bowers et al., 1997).

4. Scholarly Activities

In addition to his research activities, Prof. Boyd has established an international reputation for his text book Nonlinear Optics (Boyd, 1992), for his earlier book Radiometry (Boyd, 1983), for the edited work Contemporary Nonlinear Optics (Agrawal and Boyd, 1992), and numerous encyclopedia and review articles.

Agrawal, G. P, and R. W. Boyd, editors, Contemporary Nonlinear Optics, Academic Press, Boston, 1992.

Bowers, M. W, R. W. Boyd, A. K. Hankla, Brillouin-Enhanced Four-Wave-Mixing Vector Phase Conjugate Mirror with Beam Combining Capability, Opt. Lett., 22, 360-362 (1997)

Boyd, R. W, M. G. Raymer, and L. M. Narducci, editors, Optical Instabilities, Cambridge University Press, Cambridge, 1986.

Boyd, R. W, Radiometry and the Detection of Optical Radiation, John Wiley and Sons, New York, 1983.

Boyd, R. W, Nonlinear Optics, Academic Press, Boston, 1992

Fischer, G. L., R. W. Boyd, R. J. Gehr, S. A. Jenekhe, J. A. Osaheni, J. E. Sipe, and L. A Weller-Brophy, Enhanced Nonlinear Optical Response of Composite Materials, Phys. Rev. Lett. 74, 1871, 1995.

Gaeta, A. L., R. W. Boyd, J. R. Ackerhalt, and P. W. Milonni, Instabilities and Chaos in the Polarizations of Counterpropagating Light Fields, Phys. Rev. Lett. 58, 2432, 1987.

Gaeta, A. L. and R. W. Boyd, Quantum Noise in Phase Conjugation, Phys. Rev. Lett., 60, 2618, 1988.

Gauthier, D. J, J. Krasinski and R. W. Boyd, Observation of Resonantly Enhanced Sum-Frequency Generation Involving Sodium Rydberg States, Optics Letters 8, 211, 1983.

Gauthier, D. J, P. Narum, and R. W. Boyd, Observation of Deterministic Chaos in a Self-Pumped Phase Conjugate Mirror, Phys. Rev. Lett. 58, 16, 1987.

Gauthier, D. J., M. S. Malcuit, and R. W. Boyd, Polarization Instabilities of Counterpropagating Laser Beams in Sodium Vapor, Phys. Rev. Lett. 61, 1827, 1988.

Gauthier, D. J, R. W. Boyd, R. K. Jungquist, J. B. Lisson, and L. L. Voci, Phase-Conjugate Fizeau Interferometer, Opt. Lett. 14, 325, 1989.

Harter, D. J, P. Narum, M. G. Raymer and R. W. Boyd, Four-Wave Parametric Amplification of Rabi Sidebands in Sodium, Phys. Rev. Lett. 46, 1192, 1981.

Kauranen, M, D. J. Gauthier, M. S. Malcuit, and R. W. Boyd, Polarization Properties of Phase Conjugation by Two-Photon Resonant Degenerate Four-Wave Mixing, Phys. Rev. A 40, 1908, 1989.

MacDonald, K. R, W. R. Tompkin, and R. W. Boyd, Passive One-Way Aberration Correction Using Four-wave Mixing, Opt. Lett. 13, 663, 1988.

Maki, J. J., M. S. Malcuit, M. G. Raymer, R. W. Boyd, and P. D. Drummond, Influence of Collisional Dephasing Processes on Superfluorescence, Phys. Rev. A 40, 5135, 1989.

Maki, J. J., M. S. Malcuit, J. E. Sipe, and R. W. Boyd, Linear and Nonlinear Optical Measurements of the Lorentz Local Field, Phys. Rev. Lett. 68, 972, 1991

Malcuit, M. S, D. J. Gauthier, and R. W. Boyd, Suppression of Amplified Spontaneous Emission by the Four-Wave Mixing Process, Phys. Rev. Lett. 55, 1086 1985.

Malcuit, M. S., J. J. Maki, D. J. Simkin, and R. W. Boyd, The Transition from Superfluorescence to Amplified Spontaneous Emission, Phys. Rev. Lett., 59, 1189, 1987.

Malcuit, M. S., D. J. Gauthier, and R. W. Boyd, Vector Phase Conjugation by Two-Photon Resonant Degenerate Four-Wave Mixing, Opt. Lett., 13, 663, 1988

Nelson, R. L. and R. W. Boyd, Enhanced Electrooptic Response of Layered Composite Materials, Appl. Phys, Lett, 74, 2417, 1999.

Rzazewski, K, M. G. Raymer, and R. W. Boyd, Delay Time Statistics of Cooperative Emission in the Presence of Homogeneous Line Broadening, Phys. Rev. A, 39, 5785, 1989.

Sipe, J. E. and R. W. Boyd, Nonlinear Susceptibility of Composite Optical Materials in the Maxwell Garnett Model, Phys. Rev. A 46, 1614, 1992.

Skeldon, M. D, P. Narum, and R. W. Boyd, Non-Frequency Shifted, High-Quality Phase Conjugation with Aberrated Pump Waves by Brillouin-Enhanced Four-Wave Mixing, Opt. Lett. 12, 343, 1987.