Thomas Udem

Cavity-enhanced dual-comb spectroscopy (2009)

Bernhardt, Birgitta, Ozawa, Akira, Jacquet, Patrick, Jacquey, Marion, Kobayashi, Yohei, Udem, Thomas, ...

The sensitivity of molecular fingerprinting is dramatically improved when placing the absorbing sample in a high-finesse optical cavity, thanks to the large increase of the effective path-length. As...

Cavity-enhanced dual-comb spectroscopy (2009)

Bernhardt, Birgitta, Ozawa, Akira, Jacquet, Patrick, Jacquey, Marion, Kobayashi, Yohei, Udem, Thomas, ...

The sensitivity of molecular fingerprinting is dramatically improved when placing the absorbing sample in a high-finesse optical cavity, thanks to the large increase of the effective path-length. As...

Cavity-enhanced dual-comb spectroscopy (2009)

Bernhardt, Birgitta, Ozawa, Akira, Jacquet, Patrick, Jacquey, Marion, Kobayashi, Yohei, Udem, Thomas, ...

The sensitivity of molecular fingerprinting is dramatically improved when placing the absorbing sample in a high-finesse optical cavity, thanks to the large increase of the effective path-length. As...

Laser frequency combs for astronomical observations (2008)

Steinmetz, Tilo, Wilken, Tobias, Araujo-Hauck, Constanza, Holzwarth, Ronald, Hänsch, Theodor W., Pasquini, Luca, ...

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require...

High harmonic frequency combs for high resolution spectroscopy (2008)

Ozawa, Akira, Rauschenberger, Jens, Gohle, Christoph, Herrmann, Maximilian, Walker, David R., Pervak, Volodymyr, ...

We generated a series of harmonics in a xenon gas jet inside a cavity seeded by pulses from a Ti:sapphire mode-locked laser with a repetition rate of 10.8 MHz. Harmonics up to 19th order at 43 nm...

Laser frequency combs for astronomical observations (2008)

Steinmetz, Tilo, Wilken, Tobias, Araujo-Hauck, Constanza, Holzwarth, Ronald, Hänsch, Theodor W., Pasquini, Luca, ...

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require...

Laser frequency combs for astronomical observations (2008)

Steinmetz, Tilo, Wilken, Tobias, Araujo-Hauck, Constanza, Holzwarth, Ronald, Hänsch, Theodor W., Pasquini, Luca, ...

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require...

Laser frequency combs for astronomical observations (2008)

Steinmetz, Tilo, Wilken, Tobias, Araujo-Hauck, Constanza, Holzwarth, Ronald, Hänsch, Theodor W., Pasquini, Luca, ...

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require...

Laser frequency combs for astronomical observations (2008)

Steinmetz, Tilo, Wilken, Tobias, Araujo-Hauck, Constanza, Holzwarth, Ronald, Hänsch, Theodor W., Pasquini, Luca, ...

A direct measurement of the universe's expansion history could be made by observing in real time the evolution of the cosmological redshift of distant objects. However, this would require...

Cavity Enhanced Optical Vernier Spectroscopy, Broad Band, High Resolution, High Sensitivity (2007)

Gohle, Christoph, Stein, Björn, Schliesser, Albert, Udem, Thomas, Hänsch, Theodor W.

A femtosecond frequency comb provides a vast number of equidistantly spaced narrow band laser modes that can be simultaneously tuned and frequency calibrated with 15 digits accuracy. Our Vernier...

Future wavelength calibration standards at ESO : the Laser Frequency Comb (2007)

Araujo-Hauck, Constanza, Pasquini, Luca, Manescau, Antonio, Udem, Thomas, Hänsch, Theodor W., Holzwarth, Ronald, ...

A new technique for precise wavelength calibration of high-resolution spectrographs using frequency combs has recently been proposed. After introducing the basic concepts and advantages of this...

High-precision wavelength calibration of astronomical spectrographs with laser frequency combs (2007)

Murphy, Michael T., Udem, Thomas, Holzwarth, Ronald, Sizmann, Andreas, Pasquini, Luca, Araujo-Hauck, Costanza, ...

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such...

Future wavelength calibration standards at ESO : the Laser Frequency Comb (2007)

Araujo-Hauck, Constanza, Pasquini, Luca, Manescau, Antonio, Udem, Thomas, Hänsch, Theodor W., Holzwarth, Ronald, ...

A new technique for precise wavelength calibration of high-resolution spectrographs using frequency combs has recently been proposed. After introducing the basic concepts and advantages of this...

High-precision wavelength calibration of astronomical spectrographs with laser frequency combs (2007)

Murphy, Michael T., Udem, Thomas, Holzwarth, Ronald, Sizmann, Andreas, Pasquini, Luca, Araujo-Hauck, Costanza, ...

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such...

Future wavelength calibration standards at ESO : the Laser Frequency Comb (2007)

Araujo-Hauck, Constanza, Pasquini, Luca, Manescau, Antonio, Udem, Thomas, Hänsch, Theodor W., Holzwarth, Ronald, ...

A new technique for precise wavelength calibration of high-resolution spectrographs using frequency combs has recently been proposed. After introducing the basic concepts and advantages of this...

High-precision wavelength calibration of astronomical spectrographs with laser frequency combs (2007)

Murphy, Michael T., Udem, Thomas, Holzwarth, Ronald, Sizmann, Andreas, Pasquini, Luca, Araujo-Hauck, Costanza, ...

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such...

High-precision wavelength calibration of astronomical spectrographs with laser frequency combs (2007)

Murphy, Michael T., Udem, Thomas, Holzwarth, Ronald, Sizmann, Andreas, Pasquini, Luca, Araujo-Hauck, Costanza, ...

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such...

Future wavelength calibration standards at ESO : the Laser Frequency Comb (2007)

Araujo-Hauck, Constanza, Pasquini, Luca, Manescau, Antonio, Udem, Thomas, Hänsch, Theodor W., Holzwarth, Ronald, ...

A new technique for precise wavelength calibration of high-resolution spectrographs using frequency combs has recently been proposed. After introducing the basic concepts and advantages of this...

High-precision wavelength calibration of astronomical spectrographs with laser frequency combs (2007)

Murphy, Michael T., Udem, Thomas, Holzwarth, Ronald, Sizmann, Andreas, Pasquini, Luca, Araujo-Hauck, Costanza, ...

We describe a possible new technique for precise wavelength calibration of high-resolution astronomical spectrographs using femtosecond-pulsed mode-locked lasers controlled by stable oscillators such...

Future wavelength calibration standards at ESO : the Laser Frequency Comb (2007)

Araujo-Hauck, Constanza, Pasquini, Luca, Manescau, Antonio, Udem, Thomas, Hänsch, Theodor W., Holzwarth, Ronald, ...

A new technique for precise wavelength calibration of high-resolution spectrographs using frequency combs has recently been proposed. After introducing the basic concepts and advantages of this...

Two-photon excitation dynamics in bound two-body Coulomb systems including ac Stark shift and ionization (2006)

Haas, Martin, Jentschura, Ulrich David, Keitel, Christoph Helmut, Kolachevsky, N., Herrmann, M., Fendel, P., ...

One of the dominant systematic effects that shift resonance lines in high-precision measurements of two-photon transitions is the dynamic (ac) Stark shift. For suitable laser frequencies, the ac...

Schneller Zählen als das Licht (2006)

Gohle, Christoph, Herrmann, Maximilian, Udem, Thomas, Hänsch, Theodor W.

The frequency comb technology that was awarded the Noble Prize of Physics enables frequency measurements of highest accuracy and the development of high-precision “optical clocks”. New...

Photoionization broadening of the 1S-2S transition in a beam of atomic hydrogen (2006)

Kolachevsky, Nikolai, Haas, Martin, Jentschura, Ulrich David, Herrmann, Maximilian, Fendel, Peter, Fischer, Marc, ...

We consider the excitation dynamics of the two-photon 1S-2S transition in a beam of atomic hydrogen by 243 nm laser radiation. Specifically, we study the impact of ionization damping on the...

New Limits on the Drift of Fundamental Constants from Laboratory Measurements (2004)

Fischer,M., Kolachevsky,Nikolai, Zimmermann,Marcus, Holzwarth,Ronald, Udem,Thomas, Hänsch,Theodor W., ...

We have remeasured the absolute 1S-2S transition frequency H in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (–29±57) Hz for the...

New Limits on the Drift of Fundamental Constants from Laboratory Measurements (2004)

Fischer, M., Kolachevsky, Nikolai, Zimmermann, Marcus, Holzwarth, Ronald, Udem, Thomas, Hänsch, Theodor W., ...

We have remeasured the absolute 1S-2S transition frequency H in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (–29±57) Hz for the...

New Limits on the Drift of Fundamental Constants from Laboratory Measurements (2004)

Fischer, M., Kolachevsky, Nikolai, Zimmermann, Marcus, Holzwarth, Ronald, Udem, Thomas, Hänsch, Theodor W., ...

We have remeasured the absolute 1S-2S transition frequency H in atomic hydrogen. A comparison with the result of the previous measurement performed in 1999 sets a limit of (–29±57) Hz for the...