Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Log inSign up
Challenges
Datasets
Workspaces
Papers
Discussions
Leaderboard
Blog
Job Board
Q3AS

© 2026 Aqora Quantum S.A.S.

TermsPrivacyLegal Notice

Physical Review A

Quantum ellipsometry using correlated-photon beams

Kimani C. Toussaint, Giovanni Di Giuseppe, Kenneth J. Bycenski, Alexander V. Sergienko, Bahaa E. A. Saleh, Malvin Carl Teich

Published Aug 9, 2004• 33 citations
Publisher

Abstract

We report ellipsometric measurements made on semiconductor samples using photon-correlated beams produced by the process of spontaneous parametric down-conversion. Such a source yields higher accuracy than its quantum-limited conventional counterpart. We also show that our approach has the added advantage of not requiring an external reference sample for calibration.

DOI
10.1103/physreva.70.023801

Related papers

Entangled-photon ellipsometry

Alexander V. Sergienko, Ayman F. Abouraddy, Kimani C. Toussaint +2 more

We present a novel quantum interferometric technique to perform ellipsometric measurements. Classical ellipsometric measurements are limited in their accuracy by virtue of the need for an absolutely calibrated source and detector. Mitigating this limitation requires the use of a well-characterized reference sample. Our technique relies on the use of a non-classical optical source, namely polarization-entangled twin photons generated by spontaneous parametric down-conversion from a nonlinear crystal, in conjunction with a coincidence-detection scheme. We have demonstrated that entangled-photon ellipsometry eliminates the necessity of constructing an interferometer altogether and is thereby self-referencing. The underlying physics that leads to this remarkable result is the presence of fourth-order (coincidence) quantum interference of the photon pairs in conjuction with polarization entanglement.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Nov 18, 2003•0 citations

An experimental report on correlated-photon ellipsometry

Kimani C. Toussaint, Giovanni Di Giuseppe, Alexander V. Sergienko +2 more

Traditional ellipsometric measurements are limited in their accuracy because of the use of an external reference sample for calibration, and because of the noise inherent in the source at low light levels. We demonstrate that these limitations can be circumvented by using a non-classical source of light, namely, twin photons generated by the process of spontaneous parametric downconversion, in conjunction with a novel polarization interferometer and coincidence-counting detection scheme. The twin-photon nature of the source is a unique feature of our scheme. We are guaranteed, on the detection of a photon in one of the arms of the setup, that its twin will be in the other. We present experimental results showing how the technique operates.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Dec 9, 2003•0 citations

Entangled-photon ellipsometry

Ayman F. Abouraddy, Kimani C. Toussaint, Alexander V. Sergienko +2 more

Performing reliable measurements in optical metrology, such as those needed in ellipsometry, requires a calibrated source and detector, or a well-characterized reference sample. We present a novel interferometric technique to perform reliable ellipsometric measurements. This technique relies on the use of a nonclassical optical source, namely, polarization-entangled twin photons generated by spontaneous parametric downconversion from a nonlinear crystal, in conjunction with a coincidence-detection scheme. Ellipsometric measurements acquired with this scheme are absolute, i.e., they require neither source nor detector calibration, nor do they require a reference.

Journal of the Optical Society of America B•Apr 1, 2002•38 citations

Quantum ellipsometry

Kimani C. Toussaint, Ayman F. Abouraddy, Alexander V. Sergienko +2 more

Summary form only given. We show that, by employing entangled-photon pairs that are generated by type II spontaneous parametric down-conversion (SPDC) in a non-collinear configuration, one can obtain absolute ellipsometric data from a reflective sample. The underlying physics that permits such ellipsometric measurements resides in the fact that fourth-order (coincidence) quantum interference of the photon pairs, in conjunction with polarization entanglement, emulates an idealized classical ellipsometric setup that utilizes a source and a detector that are both calibrated absolutely.

Quantum Electronics and Laser Science Conference•Jun 25, 2003•1 citation

Ellipsometry with polarisation-entangled photons

David J. L. Graham, A. S. Parkins, Lionel R. Watkins

Polarisation-entangled photon pairs from a two crystal, type-I spontaneous parametric down conversion source are used to make accurate measurements of the ellipsometric angles of a silicon dioxide film on silicon and of internal and external reflection from BK7 glass. Since our source produces an entangled state with some mixture, a novel technique based on quantum tomography was developed to estimate the components of the density matrix for the state before and after reflection from the samples. The ellipsometric angles are readily calculated from these components and experimental measurements made on the samples were found to be in good agreement with their expected values.

Optics Express•Jan 1, 2006•26 citations

Polarization-entangled twin-photon ellipsometry

Kimani C. Toussaint, Ayman F. Abouraddy, Matthew T. Corbo +3 more

The high accuracy required in traditional ellipsometric measurements necessitates the absolute calibration of both the source and the detector. We demonstrate that these requirements can be circumvented by using a non-classical source of light, namely, a twin-photon polarization-entangled source that produces type-II spontaneous parametric down-conversion, in conjunction with a novel polarization interferometer and coincidence-counting detection scheme. Our scheme exhibits two features that obviate the requirements of a calibrated source and detector. The first is the twin-photon nature of the source; we are guaranteed, on the detection of a photon in one of the arms of the setup, that its twin will be in the other, effectively serving as calibration of the source. The second is that the polarization entanglement of the source serves as an interferometer, thereby alleviating the need for calibrating the detector. The net result is that absolute ellipsometric data from a sample may be obtained. We present preliminary experimental results showing how the technique operates.

Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE•Sep 2, 2002•1 citation
We report ellipsometric measurements made on semiconductor samples using photon-correlated beams produced by the process of spontaneous parametric down-conversion. Such a source yields higher accuracy than its quantum-limited conventional counterpart. We also show that our approach has the added advantage of not requiring an external reference sample for calibration.
We present a novel quantum interferometric technique to perform ellipsometric measurements. Classical ellipsometric measurements are limited in their accuracy by virtue of the need for an absolutely calibrated source and detector. Mitigating this limitation requires the use of a well-characterized reference sample. Our technique relies on the use of a non-classical optical source, namely polarization-entangled twin photons generated by spontaneous parametric down-conversion from a nonlinear crystal, in conjunction with a coincidence-detection scheme. We have demonstrated that entangled-photon ellipsometry eliminates the necessity of constructing an interferometer altogether and is thereby self-referencing. The underlying physics that leads to this remarkable result is the presence of fourth-order (coincidence) quantum interference of the photon pairs in conjuction with polarization entanglement.
Traditional ellipsometric measurements are limited in their accuracy because of the use of an external reference sample for calibration, and because of the noise inherent in the source at low light levels. We demonstrate that these limitations can be circumvented by using a non-classical source of light, namely, twin photons generated by the process of spontaneous parametric downconversion, in conjunction with a novel polarization interferometer and coincidence-counting detection scheme. The twin-photon nature of the source is a unique feature of our scheme. We are guaranteed, on the detection of a photon in one of the arms of the setup, that its twin will be in the other. We present experimental results showing how the technique operates.
Performing reliable measurements in optical metrology, such as those needed in ellipsometry, requires a calibrated source and detector, or a well-characterized reference sample. We present a novel interferometric technique to perform reliable ellipsometric measurements. This technique relies on the use of a nonclassical optical source, namely, polarization-entangled twin photons generated by spontaneous parametric downconversion from a nonlinear crystal, in conjunction with a coincidence-detection scheme. Ellipsometric measurements acquired with this scheme are absolute, i.e., they require neither source nor detector calibration, nor do they require a reference.
Summary form only given. We show that, by employing entangled-photon pairs that are generated by type II spontaneous parametric down-conversion (SPDC) in a non-collinear configuration, one can obtain absolute ellipsometric data from a reflective sample. The underlying physics that permits such ellipsometric measurements resides in the fact that fourth-order (coincidence) quantum interference of the photon pairs, in conjunction with polarization entanglement, emulates an idealized classical ellipsometric setup that utilizes a source and a detector that are both calibrated absolutely.
Polarisation-entangled photon pairs from a two crystal, type-I spontaneous parametric down conversion source are used to make accurate measurements of the ellipsometric angles of a silicon dioxide film on silicon and of internal and external reflection from BK7 glass. Since our source produces an entangled state with some mixture, a novel technique based on quantum tomography was developed to estimate the components of the density matrix for the state before and after reflection from the samples. The ellipsometric angles are readily calculated from these components and experimental measurements made on the samples were found to be in good agreement with their expected values.
The high accuracy required in traditional ellipsometric measurements necessitates the absolute calibration of both the source and the detector. We demonstrate that these requirements can be circumvented by using a non-classical source of light, namely, a twin-photon polarization-entangled source that produces type-II spontaneous parametric down-conversion, in conjunction with a novel polarization interferometer and coincidence-counting detection scheme. Our scheme exhibits two features that obviate the requirements of a calibrated source and detector. The first is the twin-photon nature of the source; we are guaranteed, on the detection of a photon in one of the arms of the setup, that its twin will be in the other, effectively serving as calibration of the source. The second is that the polarization entanglement of the source serves as an interferometer, thereby alleviating the need for calibrating the detector. The net result is that absolute ellipsometric data from a sample may be obtained. We present preliminary experimental results showing how the technique operates.