Directional Dynamics in the Photodissociation of Oriented Molecules

Rakitzis, T. Peter; Brom, Alrik J. van den; Janssen, Maurice H. M.

doi:10.1126/science.1094186

Cited by 148 publications

(114 citation statements)

References 29 publications

(41 reference statements)

Supporting

Mentioning

110

Contrasting

Order By: Relevance

“…Manipulating the molecular rotational degrees of freedom in gas phase by means of laser fields remains a very attractive topic in quantum control [1,2] with a wide range of applications in photochemistry extending from chemical reactivity [3,4] to nanoscale design [5,6], stereochemistry [7], surface processing [5,8], catalysis [9], and attosecond molecular dynamics [10]. Such phenomena play also a role in quantum computing [11] and high-order harmonic generation [12,13,14,15].…”

Section: Introductionmentioning

confidence: 99%

Observation of the field-free orientation of a symmetric-top molecule by terahertz laser pulses at high temperature

et al. 2016

View full text Add to dashboard Cite

We investigate experimentally and numerically the field-free orientation of the symmetric top molecule of methyl-iodide at high temperature using a terahertz radiation generated by a plasma induced by a two-color laser beam. The degree of orientation is measured from the free-induction decay emitted by the sample. The observed experimental signal is reproduced with a good accuracy by numerical simulations.

show abstract

Section: Introductionmentioning

confidence: 99%

Observation of the field-free orientation of a symmetric-top molecule by terahertz laser pulses at high temperature

et al. 2016

View full text Add to dashboard Cite

show abstract

“…Orientation of parent molecules before photolysis can provide additional information on the dynamics of the dissociation of the molecule. 8,9 Orientation of symmetric top parent molecules before dissociation can be accomplished by selecting a single ͑JKM͒ rotational state with M 0 using a hexapole state selector and retaining the projection M of the total angular momentum J on an external axis by leading the state-selected molecules into a homogeneous electric field. If one of the atoms of the parent molecule has a nonzero nuclear spin I, coupling of I to the rotational angular momentum J will reduce the effective orientation of the molecular axis.…”

Section: Introductionmentioning

confidence: 99%

Slice imaging of photodissociation of spatially oriented molecules

Lipciuc

Brom

Dinu

et al. 2005

Review of Scientific Instruments

Self Cite

View full text Add to dashboard Cite

An electrostatic ion lens to spatially orient parent molecules and to image the angular distribution of photofragments is presented. Photodissociation of laboratory-oriented molecules makes it possible to study the dynamics of the dissociation process in more detail compared to photodissociation of nonoriented molecules. Using the velocity map imaging technique in combination with the slice imaging technique, the spatial recoil distribution of the photofragments can be measured with high resolution and without symmetry restrictions. Insertion of orientation electrodes between the repeller and the extractor of a velocity mapping electrostatic lens severely distorts the ion trajectories. The position where the ions are focused by the lens, the focal length, can be very different in the directions parallel and perpendicular to the inserted orientation electrodes. The focal length depends on the exact dimensions and positions of the electrodes of the ion lens. As this dependence is different in both directions, this dependence can be used to correct for the distorted ion trajectories. We discuss the design of an electrostatic ion lens, which is able to orient parent molecules and map the velocity of the photofragments. We report sliced images of photofragments from photolysis of spatially oriented CD 3 I molecules to demonstrate the experimental combination of molecular orientation and velocity map slice imaging with good resolution.

show abstract

“…The resonance appears as a local maximum in the even-harmonic emission around 28 eV. In contrast, the odd-harmonic emission is suppressed in this spectral region through the combined effects of an asymmetric photorecombination phase and a sub-cycle Stark effect, generic for polar molecules, that we experimentally identify.Techniques for fixing molecules in space are invaluable tools for a broad range of experiments in ultrafast science [1,2]. The availability of transiently aligned molecular samples has particularly advanced strong-field and attosecond spectroscopies, providing new insights into the electronic structure of molecules and its temporal evolution [3][4][5][6][7].…”

mentioning

confidence: 99%

“…Techniques for fixing molecules in space are invaluable tools for a broad range of experiments in ultrafast science [1,2]. The availability of transiently aligned molecular samples has particularly advanced strong-field and attosecond spectroscopies, providing new insights into the electronic structure of molecules and its temporal evolution [3][4][5][6][7].…”

mentioning

confidence: 99%

Two-Pulse Field-Free Orientation Reveals Anisotropy of Molecular Shape Resonance

2014

View full text Add to dashboard Cite

We report the observation of macroscopic field-free orientation, i.e. more than 73 % of CO molecules pointing in the same direction. This is achieved through an all-optical scheme operating at high particle densities (> 10 17 cm −3 ) that combines a one-color (ω) and a two-color (ω + 2ω) non-resonant femtosecond laser pulses. We show that the achieved orientation solely relies on the hyperpolarizability interaction as opposed to an ionization-depletion mechanism thus opening a wide range of applications. The achieved strong orientation enables us to reveal the molecularframe anisotropies of the photorecombination amplitudes and phases caused by a shape resonance. The resonance appears as a local maximum in the even-harmonic emission around 28 eV. In contrast, the odd-harmonic emission is suppressed in this spectral region through the combined effects of an asymmetric photorecombination phase and a sub-cycle Stark effect, generic for polar molecules, that we experimentally identify.Techniques for fixing molecules in space are invaluable tools for a broad range of experiments in ultrafast science [1,2]. The availability of transiently aligned molecular samples has particularly advanced strong-field and attosecond spectroscopies, providing new insights into the electronic structure of molecules and its temporal evolution [3][4][5][6][7]. High-harmonic spectroscopy (HHS) provides a new access to the rich structures of photoionization continua, such as Cooper minima [8][9][10][11] and shape resonances [11][12][13]. The investigation of the inherent structural and dynamical anisotropies of polar molecules has however been prevented by the difficulty of orienting molecules. Interesting phenomena tied to polar molecules include the predicted recombination-site dependence of structural minima [14,15] and attosecond charge migration [16][17][18] triggered by strong-field ionization. Here, we demonstrate a protocol for molecular orientation which achieves macroscopic field-free orientation and exploit this progress to probe the anisotropy of photorecombination dipole moments at a molecular shape resonance.Successful approaches to laser-induced molecular orientation include the combination of an electrostatic field with a rapidly turned-off laser field [19], alignment in combination with quantum-state selection and a weak dc-field [20][21][22][23], adiabatic [24] and impulsive two-color orientation [25][26][27]. All of these techniques are subject to substantial limitations: The presence of electric fields may alter the electronic structure of the molecule, its photo-induced dynamics or the subsequent probing process. The low particle densities available after quantumstate selection make the application of such techniques to high-harmonic and attosecond spectroscopies challenging to impossible. The two-color scheme [22,25], recently applied to HHS [26,27], relies on an ionization-depletion mechanism [28] and thus ties the achievable degree of orientation to the ionization fraction of the sample. This fact does not only limi...

show abstract

Directional Dynamics in the Photodissociation of Oriented Molecules

Cited by 148 publications

References 29 publications

Observation of the field-free orientation of a symmetric-top molecule by terahertz laser pulses at high temperature

Observation of the field-free orientation of a symmetric-top molecule by terahertz laser pulses at high temperature

Slice imaging of photodissociation of spatially oriented molecules

Two-Pulse Field-Free Orientation Reveals Anisotropy of Molecular Shape Resonance

Contact Info

Product

Resources

About