Laser-induced Coulomb explosion, geometry modification and reorientation of carbon dioxide

Bryan, William A.; Sanderson, Joseph; El-Zein, A.A.A.; Newell, W R; Taday, Philip F.; Langley, A. J.

doi:10.1088/0953-4075/33/4/312

Cited by 53 publications

(55 citation statements)

References 29 publications

(90 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…As a consequence, the excited or ionized molecule may undergo severe geometrical reconfiguration and may also break into several fragments or form new chemical bonds. Because of the importance of CO 2 in many research disciplines, strongfield induced reactions of CO 2 have been experimentally studied with ultrashort lasers by several research groups.However, these studies mainly focused on the topic of ionization and dissociation [16]. In this paper, for the first time to our knowledge, we report on the direct observation of O + 2 formation from CO 2 induced by strong laser pulses with a reaction microscope.…”

mentioning

confidence: 93%

See 1 more Smart Citation

Molecular oxygen observed by direct photoproduction from carbon dioxide

et al. 2017

View full text Add to dashboard Cite

Oxygen (O2 ) is one of the most important elements required to sustain life. The concentration of O2 on Earth has been accumulated over millions of years and has a direct connection with that of CO2 . Further, CO2 plays an important role in many other planetary atmospheres. Therefore, molecular reactions involving CO2 are critical for studying the atmospheres of such planets. Existing studies on the dissociation of CO2 are exclusively focused on the C-O bond breakage. Here we report first experiments on the direct observation of molecular Oxygen formation from CO2 in strong laser fields with a reaction microscope. Our accompanying simulations suggest that CO2 molecules may undergo bending motion during and after strong-field ionization which supports the molecular Oxygen formation process. The observation of the molecular Oxygen formation from CO2 may trigger further experimental and theoretical studies on such processes with laser pulses, and provide hints in studies of the O2 and O + 2 abundance in CO2 -dominated planetary atmospheres.PACS numbers: 33.80. Gj, 42.50.Hz, O 2 production is one of the most important processes for the biosphere of the Earth.Oxygen molecules are mainly generated via the photosynthesis by green plants and algae from carbon dioxide and water:. CO 2 is not only important for the atmosphere on Earth, it is also the dominant compound of the atmosphere on other planets, such as Mars and Venus. One of the most crucial tasks for the quest to establish a human settlement on Mars is the production of O 2 [2]. Because more than 95% of the atmosphere on Mars is CO 2 , it will be extremely helpful if O 2 can be produced directly from CO 2 . In the past, it was observed that dissociation of CO 2 via absorption of photons leads to carbon monoxide (CO) and oxygen atoms (O) [3]. However, theoretical simulations suggested the possibility of generating O 2 through the dissociation of a CO 2 molecule [4]. A recent experiment showed the evidence of O 2 formation from CO 2 molecules after UV excitation through the detection of C + [5]. So far, O 2 formation from CO 2 has not been directly observed.In the past decade, intense ultrashort laser pulses have been successfully applied to trigger and control molecular reactions such as dissociation and isomerization [6][7][8][9][10][11][12][13][14][15]. When a molecule interacts with a strong laser field, electrons from outer molecular orbitals can be excited or removed through tunneling or over-the-barrier ionization which may prepare the molecule in an excited state or a state with a certain charge. As a consequence, the excited or ionized molecule may undergo severe geometrical reconfiguration and may also break into several fragments or form new chemical bonds. Because of the importance of CO 2 in many research disciplines, strongfield induced reactions of CO 2 have been experimentally studied with ultrashort lasers by several research groups.However, these studies mainly focused on the topic of ionization and dissociation [16]. In this paper, for the first...

show abstract

mentioning

confidence: 93%

“…However, these studies mainly focused on the topic of ionization and dissociation [16]. In this paper, for the first time to our knowledge, we report on the direct observation of O + 2 formation from CO 2 induced by strong laser pulses with a reaction microscope.…”

mentioning

confidence: 93%

Molecular oxygen observed by direct photoproduction from carbon dioxide

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Отметим, что взаимодействие лазерного излуче-ния с пространственно-ориентированными молекулами исследуется экспериментально во многих работах (см., например, [28][29][30][31]). Изменение геометрических параметров в многоатом-ных молекулах наблюдалось при изучении кулоновского взрыва (см., например, [32][33][34][35][36][37][38][39][40]). Такое изменение со-провождается в общем случае изменением нормальных координат, определяющих положения ядер атомов, вхо-дящих в состав молекулы.…”

unclassified

“…Изменение геометрических параметров в многоатом-ных молекулах наблюдалось при изучении кулоновского взрыва (см., например, [32][33][34][35][36][37][38][39][40]). Такое изменение со-провождается в общем случае изменением нормальных координат, определяющих положения ядер атомов, вхо-дящих в состав молекулы.…”

unclassified

Изменение Нормальных Координат И Геометрических Параметров Молекулы В Лазерном Поле

Корнев¹,

Суворов²,

Чернов³

et al. 2018

Журнал Технической Физики

View full text Add to dashboard Cite

Поступила в редакцию 21.08.2017 г. Получены общие формулы, описывающие изменение равновесных расстояний, валентных углов и частот колебаний многоатомной молекулы в сильном лазерном поле. Показано, что во втором порядке по напряженности поля координаты нормальных колебаний молекулы не изменяются. Для нелинейной трехатомной молекулы типа A 2 B изменение геометрических характеристик и частот колебаний найдены в явном виде. одетого полем" атома при рас-сеянии на нем электрона в поле лазерного излучения (laser-assisted electron scattering, LAES), теоретически рассмотренного в работе [16]. Рассматриваемая в на-стоящей работе теория представляет собой вариант концепции " одетой полем" многоатомной молекулы, в которой происходит индуцированное полем изменение геометрических и спектроскопических характеристик. Это изменение связано с тем, что вследствие поляри-зуемости молекулы ее энергия во внешнем поле изме-няется. Поэтому равновесная конфигурация молекулы в поле, соответствующая минимуму потенциальной энер-гии, может отличаться от равновесной конфигурации свободной молекулы.При рассмотрении этого эффекта мы используем метод, предложенный в [17] и развитый в [18] для расчета неадиабатических восприимчивостей молекул в постоянном поле. Основное отличие постоянного поля от переменного в данном случае состоит в том, что в постоянном поле для полярных молекул возникают поправки к энергии молекулы нечетных порядков по на-пряженности поля, которых нет в переменных полях ИК и оптических частот [19]. Следует также отметить неади-абатическое исследование оптических свойств простей-ших молекул, проведенное в работе [20] вариационным методом с использованием осцилляторных функций. Обзор дальнейших работ этих авторов, в частности, проявление изменений геометрических параметров и колебательных спектров молекул (иными словами, ко-лебательного эффекта Штарка [21]) в эффекте Керра, а также в генерации второй (в электрическом поле) и третьей гармоник дан в работе [22].Рассмотрение данного явления для двухатомных мо-лекул было проведено в работе [23]. В этом простейшем случае поляризуемость молекулы приводит к измене-нию равновесного межъядерного расстояния и частот ядерных колебаний. Это, в свою очередь, приводит к изменению факторов Франка-Кондона, что проявляется в изменениях вероятностей электромагнитных перехо-дов молекулы. Проведенные в работах [24-27] расчеты вероятностей туннельной ионизации ряда двухатомных молекул показали, что из-за указанного изменения фак-торов Франка-Кондона вероятность ионизации молекул изменяется до двух раз.В многоатомных молекулах в отличие от двухатомных внешнее поле изменяет не только межъядерные рассто-яния и частоты колебаний ядер, но и валентные углы. Поскольку поляризуемость молекулы является тензор-ной величиной, изменение всех этих параметров зави-сит от ориентации молекулы относительно направления поля. Отметим, что взаимодействие лазерного излуче-ния с пространственно-ориентированными молекулами исследуется экспериментально во многих работах (см., например, [28][29][30][31]).Изменение геом...

show abstract

“…Subsequent to interacting with the laser pulse, the fast ion beam was deflected in a 45 ± parallel plate analyzer, such that ionized products could be detected in an off-axis channel electron multiplier, while the primary Ar 1 beam was collected in a well-baffled Faraday cup. Neutral Ar spectra were collected using a Wiley-McLaren -type time of flight mass spectrometer employing an identical optical configuration to that used in the ion beam apparatus [25]. Figure 1a shows a typical 10 3 shot averaged time-offlight spectrum obtained from neutral Ar at an intensity close to the expected limit of the nonsequential regime for production of Ar 31 .…”

mentioning

confidence: 99%

Suppression of Multiple Ionization of Atomic Ions in Intense Ultrafast Laser Pulses

Greenwood

Johnston²,

McKenna³

et al. 2002

Phys. Rev. Lett.

View full text Add to dashboard Cite

The interaction of an intense laser field with a beam of atomic ions has been investigated experimentally for the first time. The ionization dynamics of Ar 1 ions and Ar neutrals in a 60 fs, 790 nm laser pulse have been compared and contrasted at intensities up to 10 16 W cm 22 . Our results show that nonsequential ionization from an Ar 1 target is strongly suppressed compared with that from the corresponding neutral target. We have also observed for the first time the strong field ionization of high lying target metastable levels in the Ar 1 beam. DOI: 10.1103/PhysRevLett.88.233001 PACS numbers: 32.80.Fb There is considerable current interest in the interaction of high intensity ͑10 13 10 18 W cm 22 ͒ radiation with dilute matter, where the external electric field strength becomes comparable to molecular bond and valance electron binding strengths. Studies have been carried out with targets of atoms, molecules, clusters [1], and most recently molecular ions [2,3], in order to elucidate the new physics observable in this highly nonlinear regime. These include the study of high harmonic generation [4], strong field effects in molecular dissociation, and the enhancement of multiple ionization in atoms [5,6]. Work is currently underway to generate attosecond pulses through harmonic generation [7,8], and coherent x-ray generation could be possible for highly charged ions in the presence of superintense fields [9,10].Both experiment and theory have shown that, in femtosecond laser pulses, multiple ionization of atoms is enhanced by nonsequential processes [5,6,11,12]. The physical model which best describes the observed behavior is known as the "atomic antenna" [13] or "recollision" [14,15] model. In this picture the first electron is removed from the atom by tunneling through the barrier created by interaction of the external field with the atomic potential. This electron is then accelerated in the external field and, depending on the initial phase, can return to the singly charged ion with energies up to 3.17U P [6], where U P is the classical ponderomotive energy in the field. Multiple ionization is thus via electron interaction with the ionic core. Evidence for this mechanism includes large reductions in nonsequential ionization rates for circularly polarized fields and more recently from the momentum distribution of the recoil ions [16,17], and coincidence measurements between ions and ejected electrons [18]. However, it has proved difficult to predict quantitative yields for the product ions without using large-scale calculations through the S-matrix approach [19] or by obtaining a time-dependent solution of the Schrödinger equation [20].By including the effects of excitation from the recollision followed by tunneling [21] and taking into account the Coulomb focusing on the active electron [22], better agreement with experiment has been obtained. The importance of multiple returns to the core has been demonstrated experimentally by a reduction in nonsequential ionization when few cycle pulses are used [23]....

show abstract

Laser-induced Coulomb explosion, geometry modification and reorientation of carbon dioxide

Cited by 53 publications

References 29 publications

Molecular oxygen observed by direct photoproduction from carbon dioxide

Molecular oxygen observed by direct photoproduction from carbon dioxide

Изменение Нормальных Координат И Геометрических Параметров Молекулы В Лазерном Поле

Suppression of Multiple Ionization of Atomic Ions in Intense Ultrafast Laser Pulses

Contact Info

Product

Resources

About