An ultrafast X-ray glance into photoacid electronic structure
2022-03-30
Photoacids are molecules that release a proton upon electronic excitation, thus enhancing the acidity of a liquid. Pioneering work by Theodor Förster has shown the direct relationship between the wavelength position of optical absorption and acidity properties with which the increase in acidity in the first electronic excited state can be quantified.
Successful experiments with stored ions in DESIREE
2022-03-25
In November 2021, Michael Gatchell's experiment showed that fragments from collisions in the interstellar medium can help form new, larger molecules. Here, DESIREE Director Henning Schmidt reports on some recent successes.
New simulation recreates the entire evolution of the Near Universe
2022-03-25
An international research team, including a researcher of Stockholm University, has carried out the most extensive simulation of the Near Universe, covering distances of up to 600 million lightyears from Earth.
Optical nano cavities: a control knob for tuning photo-chemical reactions on a quantum level
2021-02-12
Researchers at Fysikum have theoretically investigated the light activated hydrogen abstraction reaction of pyrrole in an optical nano cavity. The electronic excitation of pyrrole with UV light triggers the hydrogen detachment reaction along the NH bond. Their latest paper investigates how strong light-matter coupling of a tightly confined electromagnetic mode can be used to steer this reaction. The results suggest that the cavity can hugely influence the reaction efficiency and open up alternative reaction pathways.
Water’s Heat Capacity Becomes Extreme in Supercooled Conditions
2021-02-08
Using x-ray lasers, researchers at Stockholm University have developed a new ultrafast calorimetry technique to measure the heat capacity (Cp) of water down to 228 K. The finding is that Cp increases dramatically below 240 K and reach a maximum at around 230 K indicating an extreme amount of entropy fluctuations. The results are consistent with existence of a critical point at temperatures around 210-215 K and at pressures 800-1000 bar. Their findings are published this week in the Proceedings of the National Academy (US).
Monitoring coherent light-matter interaction in the strong-coupling limit
2021-01-29
In a recently published article in Optics Communications, Themis Mavrogordatos, Fysikum, and Cristóbal Lledó, University College London (UCL), address the coherence of side-scattering in the driven dissipative Jaynes–Cummings (JC) model. They link atomic fluorescence to the multi-photon resonance operation of the JC oscillator and point to the differences from the scattered field of ordinary resonance fluorescence. They show that fluorescence uncovers the details of the cascaded process organizing multi-photon blockade.
Hiranya Peiris awarded by the Royal Astronomical Society
2021-01-12
Hiranya Peiris, professor of cosmoparticle physics at the Department of Physics and director of the Oskar Klein Center, Stockholm University, has been awarded with the Eddington Medal 2021 by the Royal Astronomical Society for her ground-breaking exploration of the origins of the Universe.
Activity descriptors of nickel-iron oxygen evolution electrocatalysts in the presence of cations
2020-12-10
The oxygen evolution reaction (OER) is a key process that enables the storage of renewable energies in the form of chemical fuels. Electrolyte alkali metal cations have been shown to modify the activity and reaction intermediates in OER; however, the exact mechanism was not understood – until recently.
Hiranya Peiris is awarded the Max Born Medal and Prize 2021
2021-01-12
Hiranya Peiris receives the award for her outstanding contribution in cosmology, where she has created new interdisciplinary connections between cosmology and high-energy physics.
Two liquids of water exist
2020-12-01
Using x-ray lasers, researchers at Stockholm University have been able to follow the transformation between two distinct different liquid states of water at around -63 Centigrade, both being made of H2O molecules. Even though the two liquids can only be studied under extreme conditions, their existence strongly influences many of waters unique properties in our daily life. Their findings are published in the journal Science.
Exploring the collective and individual channels of light-matter interaction
2020-11-12
In two reports published this month, we investigate atomic emission and light-matter correlations in absorptive optical bistability. From a linearized treatment of quantum fluctuations we show a visible departure from classical behavior and propose an experimental setup to extract the otherwise hidden collective degree of freedom coupled to the intracavity field.
Electron–spin dynamics studied on its natural time-scale
2020-10-09
By using extremely short light pulses and coincidence technology, researchers from several Swedish universities have managed to follow the dynamic process when the electron's spin - its rotation around its own axis - controls how an atom absorbs light.
First result from DESIREE using merged-beams
2020-09-16
The DESIREE facility, with its unique design of two storage rings with a common straight section was constructed in order to study reactions between pairs of oppositely charged atomic or molecular ions. The results of the first such experiment have recently been published.
Spin nutation in magnetic materials observed for the first time
2020-09-29
For the first time, spin nutation in magnetic materials has been observed. The discovery could impact the way digital information is saved and lead to a faster, more compact and more energy-efficient technology.
The rarest element on earth is studied in detail
2020-08-18
Can the rarest element on earth, astatine, be used to treat tumors? A new study published in Nature Communications is the first to measure in detail the electron affinity of astatine that is relevant for development of targeted alpha therapy.
X-rays indicate that water can behave like a liquid crystal
2020-08-11
Scientists at Stockholm University have discovered that water can exhibit a similar behavior like a liquid crystal when illuminated with laser light. This effect originates by the alignment of water molecules, which exhibit a mixture of low- and high-density domains that are more or less prone to alignment. Can this discovery have future technological applications?
Excess Events observed in Dark Matter Experiment
2020-06-18
Scientists from the international XENON collaboration announced today that data from their XENON1T, the world's most sensitive dark matter experiment, show a surprising excess of events.
Inferring entropy production from short time series
2020-04-28
Recent research at Fysikum, published in Physical Review Letters, discovers a simple method to quantify dissipation in microscopic non-equilibrium systems by analysing short time series data.
New Twist on Strongly Correlated Quantum Matter
2020-04-24
Exotic new states of quantum matter form in twisted graphene systems, according to research from Fysikum published as Editors’ suggestion in Physical Review Letters.
Speeding-up quantum computing using giant atomic ions
2020-04-15
Trapped Rydberg ions can be the next step towards scaling up quantum computers to sizes where they can be practically usable, a new study in Nature shows.
Hiranya Peiris is awarded the Göran Gustafsson Prize
2020-03-03
The Göran Gustafsson Prize in Physics is awarded to Hiranya Peiris, "for her innovative research on the dynamics of the early universe, which links cosmological observations to basic physics".
Mapping out the properties of antimatter
2020-02-21
Why does anything exist? That is really the fundamental question we try to answer through high-precision studies of antimatter. All matter that builds up the universe we see should really have been annihilated through contact with it mirror image – antimatter. Clearly, this has not happened, which is one of the great still unsolved mysteries of Physics.
Filming a quantum measurement
2020-12-17
Does a quantum state collapse instantly during measurement? And if not, how much time does the measurement process take and what is the quantum state of the system at any intermediate step?
SU researcher receives funding for new artificial photosynthsis project
2020-02-07
Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which energy is converted to light energy. This is a natural phenomenon and it is most common in deep sea living creatures.
KAW grants awarded to three projects in which researchers from Fysikum are involved
2019-10-11
The Knut and Alice Wallenberg fundation has announced 20 ground-breaking research projects to receive grants for a total of 640 million SEK. Among them three projects include several researchers at the Department of Physics as co-investigator.
Revealing the quantum energy scale of light-matter interaction in a thermodynamic limit
2019-10-01
In this work, we approach a limit probing the nature of light-matter interaction with strong coupling, revealing the significance of quantum fluctuations. We monitor the output channel of a paradigmatic oscillator in quantum optics, described by the Jaynes-Cummings model, subject to an imposed coherent driving field. Drive and decay create the landscape in which the quantum and classical frames are intertwined.
Interview with Igor Pikovski
2019-10-11
Igor Pikovski recently joined Stockholm University as assistant professor in the Department of Physics. He is a theoretical physicist in the field of quantum optics and quantum information theory. His main interest is the interface between quantum physics at low energies and gravity, especially in a regime that can be accessed in laboratory experiments.
Corner States of Light
2019-10-07
Researchers at Stockholm University have managed to create a new kind of light wave whose unique properties may become important e.g. in future communication technology. In a recently published article in Nature Photonics, they have shown how ideas from theoretical quantum and materials physics can be realised in a completely different context, namely in optical waveguides.
European grant for novel sustainable energy supply and storage awarded to Fysikum
2019-08-22
An European wide network, involving Markus Kowalewski and Michel Odelius from the Division of Chemical Physics at Fysikum, has received funding from the European Research Council (ERC). The project, which includes partners from 8 different countries, will investigate charge carrier dynamics in materials relevant for novel energy supply and storage.
The extreme of rarity
2019-04-30
OKC researchers helped reveal the rarest nuclear reaction now known to mankind. To observe this ultra-rare process, XENON1T watched a tonne of ultra-pure liquid xenon for a year. The experiment was featured on the cover of the scientific journal 'Nature'
Efficiency fluctuations in microscopic machines
2019-04-15
Results of a recent study by physicists from Stockholm University in collaboration with researchers at Nordita and the University of Bielefeld, provide a general understanding of the efficiency fluctuations in microscopic machines.
Steering is an essential feature of non-locality in quantum theory
2018-10-15
A physical theory is called non-local when observers can produce instantaneous effects over distant systems. Non-local theories rely on two fundamental effects: local uncertainty relations and steering of physical states at a distance. In quantum mechanics, the former one dominates the other in non-local games. A new study proved that the entanglement-based steering also plays an important role.
Topology of non-Hermitian systems unraveled
2018-10-02
The study of topological materials has been an important task in condensed matter physics over the past few decades and was the subject of the 2016 Nobel prize in physics. Recent experiments and theoretical works have shown that unexpected phenomena occur in many open, non-equilibrium and complex systems that can be described using non-Hermitian physics.
Two prestigious Quantum Technology grants for Fysikum
2019-10-07
Fysikum has been very successful in the highly competitive QuantERA ERA-NET Confund call in Quantum Technologies. Two proposals coordinated by Ana Predojevic and Markus Hennrich, at Fysikum, Stockholm University, have been selected for funding.
The Ultrafast Dance of Liquid Water
2018-05-15
It is normally considered that water molecules in the liquid state move randomly on ultrafast timescales due to thermal fluctuations. Researchers at Stockholm University have now discovered an unexpected correlated motion in water dynamics on a sub-100 femtoseconds timescale.
An ultrafast X-ray glance into photoacid electronic structure
2022-03-30
Photoacids are molecules that release a proton upon electronic excitation, thus enhancing the acidity of a liquid. Pioneering work by Theodor Förster has shown the direct relationship between the wavelength position of optical absorption and acidity properties with which the increase in acidity in the first electronic excited state can be quantified.
Successful experiments with stored ions in DESIREE
2022-03-25
In November 2021, Michael Gatchell's experiment showed that fragments from collisions in the interstellar medium can help form new, larger molecules. Here, DESIREE Director Henning Schmidt reports on some recent successes.
New simulation recreates the entire evolution of the Near Universe
2022-03-25
An international research team, including a researcher of Stockholm University, has carried out the most extensive simulation of the Near Universe, covering distances of up to 600 million lightyears from Earth.
Photodissociation of ironpentacarbonyl acts as a carbonmonoxide geyser
2022-03-25
Transition metal complexes are efficiently acting as catalysts and are used for energy conversion in photochemical processes because of easily accessible close-lying electronic states.
Optical nano cavities: a control knob for tuning photo-chemical reactions on a quantum level
2021-02-12
Researchers at Fysikum have theoretically investigated the light activated hydrogen abstraction reaction of pyrrole in an optical nano cavity. The electronic excitation of pyrrole with UV light triggers the hydrogen detachment reaction along the NH bond. Their latest paper investigates how strong light-matter coupling of a tightly confined electromagnetic mode can be used to steer this reaction. The results suggest that the cavity can hugely influence the reaction efficiency and open up alternative reaction pathways.
Water’s Heat Capacity Becomes Extreme in Supercooled Conditions
2021-02-08
Using x-ray lasers, researchers at Stockholm University have developed a new ultrafast calorimetry technique to measure the heat capacity (Cp) of water down to 228 K. The finding is that Cp increases dramatically below 240 K and reach a maximum at around 230 K indicating an extreme amount of entropy fluctuations. The results are consistent with existence of a critical point at temperatures around 210-215 K and at pressures 800-1000 bar. Their findings are published this week in the Proceedings of the National Academy (US).
Monitoring coherent light-matter interaction in the strong-coupling limit
2021-01-29
In a recently published article in Optics Communications, Themis Mavrogordatos, Fysikum, and Cristóbal Lledó, University College London (UCL), address the coherence of side-scattering in the driven dissipative Jaynes–Cummings (JC) model. They link atomic fluorescence to the multi-photon resonance operation of the JC oscillator and point to the differences from the scattered field of ordinary resonance fluorescence. They show that fluorescence uncovers the details of the cascaded process organizing multi-photon blockade.
Hiranya Peiris awarded by the Royal Astronomical Society
2021-01-12
Hiranya Peiris, professor of cosmoparticle physics at the Department of Physics and director of the Oskar Klein Center, Stockholm University, has been awarded with the Eddington Medal 2021 by the Royal Astronomical Society for her ground-breaking exploration of the origins of the Universe.
Top 10 breakthrough of the year - research from Stockholm University noticed by Physics World
2020-12-17
The article "Tracking the dynamics of an ideal quantum measurement" has among 550 new research papers been selected as a top 10 breakthrough of the year by Physics World.
Activity descriptors of nickel-iron oxygen evolution electrocatalysts in the presence of cations
2020-12-10
The oxygen evolution reaction (OER) is a key process that enables the storage of renewable energies in the form of chemical fuels. Electrolyte alkali metal cations have been shown to modify the activity and reaction intermediates in OER; however, the exact mechanism was not understood – until recently.
Hiranya Peiris is awarded the Max Born Medal and Prize 2021
2021-01-12
Hiranya Peiris receives the award for her outstanding contribution in cosmology, where she has created new interdisciplinary connections between cosmology and high-energy physics.
Exploring the collective and individual channels of light-matter interaction
2020-11-12
In two reports published this month, we investigate atomic emission and light-matter correlations in absorptive optical bistability. From a linearized treatment of quantum fluctuations we show a visible departure from classical behavior and propose an experimental setup to extract the otherwise hidden collective degree of freedom coupled to the intracavity field.
Electron–spin dynamics studied on its natural time-scale
2020-10-09
By using extremely short light pulses and coincidence technology, researchers from several Swedish universities have managed to follow the dynamic process when the electron's spin - its rotation around its own axis - controls how an atom absorbs light.
First result from DESIREE using merged-beams
2020-09-16
The DESIREE facility, with its unique design of two storage rings with a common straight section was constructed in order to study reactions between pairs of oppositely charged atomic or molecular ions. The results of the first such experiment have recently been published.
Spin nutation in magnetic materials observed for the first time
2020-09-29
For the first time, spin nutation in magnetic materials has been observed. The discovery could impact the way digital information is saved and lead to a faster, more compact and more energy-efficient technology.
The rarest element on earth is studied in detail
2020-08-18
Can the rarest element on earth, astatine, be used to treat tumors? A new study published in Nature Communications is the first to measure in detail the electron affinity of astatine that is relevant for development of targeted alpha therapy.
X-rays indicate that water can behave like a liquid crystal
2020-08-11
Scientists at Stockholm University have discovered that water can exhibit a similar behavior like a liquid crystal when illuminated with laser light. This effect originates by the alignment of water molecules, which exhibit a mixture of low- and high-density domains that are more or less prone to alignment. Can this discovery have future technological applications?
Excess Events observed in Dark Matter Experiment
2020-06-18
Scientists from the international XENON collaboration announced today that data from their XENON1T, the world's most sensitive dark matter experiment, show a surprising excess of events.
Inferring entropy production from short time series
2020-04-28
Recent research at Fysikum, published in Physical Review Letters, discovers a simple method to quantify dissipation in microscopic non-equilibrium systems by analysing short time series data.
New Twist on Strongly Correlated Quantum Matter
2020-04-24
Exotic new states of quantum matter form in twisted graphene systems, according to research from Fysikum published as Editors’ suggestion in Physical Review Letters.
Speeding-up quantum computing using giant atomic ions
2020-04-15
Trapped Rydberg ions can be the next step towards scaling up quantum computers to sizes where they can be practically usable, a new study in Nature shows.
Mapping out the properties of antimatter
2020-02-21
Why does anything exist? That is really the fundamental question we try to answer through high-precision studies of antimatter. All matter that builds up the universe we see should really have been annihilated through contact with it mirror image – antimatter. Clearly, this has not happened, which is one of the great still unsolved mysteries of Physics.
Filming a quantum measurement
2020-12-17
Does a quantum state collapse instantly during measurement? And if not, how much time does the measurement process take and what is the quantum state of the system at any intermediate step?
SU researcher receives funding for new artificial photosynthsis project
2020-02-07
Bioluminescence is the production and emission of light by a living organism as the result of a chemical reaction during which energy is converted to light energy. This is a natural phenomenon and it is most common in deep sea living creatures.
KAW grants awarded to three projects in which researchers from Fysikum are involved
2019-10-11
The Knut and Alice Wallenberg fundation has announced 20 ground-breaking research projects to receive grants for a total of 640 million SEK. Among them three projects include several researchers at the Department of Physics as co-investigator.
Revealing the quantum energy scale of light-matter interaction in a thermodynamic limit
2019-10-01
In this work, we approach a limit probing the nature of light-matter interaction with strong coupling, revealing the significance of quantum fluctuations. We monitor the output channel of a paradigmatic oscillator in quantum optics, described by the Jaynes-Cummings model, subject to an imposed coherent driving field. Drive and decay create the landscape in which the quantum and classical frames are intertwined.
Interview with Igor Pikovski
2019-10-11
Igor Pikovski recently joined Stockholm University as assistant professor in the Department of Physics. He is a theoretical physicist in the field of quantum optics and quantum information theory. His main interest is the interface between quantum physics at low energies and gravity, especially in a regime that can be accessed in laboratory experiments.
Corner States of Light
2019-10-07
Researchers at Stockholm University have managed to create a new kind of light wave whose unique properties may become important e.g. in future communication technology. In a recently published article in Nature Photonics, they have shown how ideas from theoretical quantum and materials physics can be realised in a completely different context, namely in optical waveguides.
European grant for novel sustainable energy supply and storage awarded to Fysikum
2019-08-22
An European wide network, involving Markus Kowalewski and Michel Odelius from the Division of Chemical Physics at Fysikum, has received funding from the European Research Council (ERC). The project, which includes partners from 8 different countries, will investigate charge carrier dynamics in materials relevant for novel energy supply and storage.
The extreme of rarity
2019-04-30
OKC researchers helped reveal the rarest nuclear reaction now known to mankind. To observe this ultra-rare process, XENON1T watched a tonne of ultra-pure liquid xenon for a year. The experiment was featured on the cover of the scientific journal 'Nature'
Efficiency fluctuations in microscopic machines
2019-04-15
Results of a recent study by physicists from Stockholm University in collaboration with researchers at Nordita and the University of Bielefeld, provide a general understanding of the efficiency fluctuations in microscopic machines.
Steering is an essential feature of non-locality in quantum theory
2018-10-15
A physical theory is called non-local when observers can produce instantaneous effects over distant systems. Non-local theories rely on two fundamental effects: local uncertainty relations and steering of physical states at a distance. In quantum mechanics, the former one dominates the other in non-local games. A new study proved that the entanglement-based steering also plays an important role.
Topology of non-Hermitian systems unraveled
2018-10-02
The study of topological materials has been an important task in condensed matter physics over the past few decades and was the subject of the 2016 Nobel prize in physics. Recent experiments and theoretical works have shown that unexpected phenomena occur in many open, non-equilibrium and complex systems that can be described using non-Hermitian physics.
Two prestigious Quantum Technology grants for Fysikum
2019-10-07
Fysikum has been very successful in the highly competitive QuantERA ERA-NET Confund call in Quantum Technologies. Two proposals coordinated by Ana Predojevic and Markus Hennrich, at Fysikum, Stockholm University, have been selected for funding.
The Ultrafast Dance of Liquid Water
2018-05-15
It is normally considered that water molecules in the liquid state move randomly on ultrafast timescales due to thermal fluctuations. Researchers at Stockholm University have now discovered an unexpected correlated motion in water dynamics on a sub-100 femtoseconds timescale.
