News Center

Synchronized Lasers Measure How Light Changes Matter

How matter responds to light lies at the core of vision, photosynthesis, solar cells and light-emitting diodes, and many other fields of scientific and practical import. But until now, it hasn’t been possible to see just how light does it. Berkeley Lab scientists have used SLAC’s Linac Coherent Light for the first demonstration that x-ray and optical wave mixing reveals not only structure but evolving charge states on the atomic scale.

BELLA Laser Achieves World Record Power at One Pulse Per Second

The laser system for BELLA, the Berkeley Lab Laser Accelerator, recently delivered a petawatt of power – a quadrillion watts – in a pulse just 40 femtoseconds long – a quadrillionth of a second — at a rate of one pulse per second. No other laser system has achieved this peak power at this rapid pulse rate. BELLA’s laser should soon be driving electron beams to 10-billion-electron-volt energies in an accelerator just one meter long.

A New Tool to Attack the Mysteries of High-Temperature Superconductivity

Using ultrafast lasers, Berkeley Lab scientists have tackled the long-standing mystery of how Cooper pairs form in high-temperature superconductors. With pump and probe pulses spaced just trillionths of a second apart, the researchers used photoemission spectroscopy to map rapid changes in electronic states across the superconducting transition, revealing relationships of energy and momentum never seen before in these promising, but stubborn, complex materials.

APEX: At the Forefront of What’s Needed for the Next Generation of Light Sources

An extraordinary “front end” for the next generation of light sources is taking shape at Berkeley Lab’s Beam Test Facility. APEX, an electron gun that will produce a continuous beam of tight electron bunches at the unprecedented repetition rate of a million bunches a second, is well on the way to becoming the must-have source for superconducting linear accelerators to power future free electron lasers.

The Next Big Step Toward Atom-Specific Dynamical Chemistry

Chemists hope to understand precisely how electrical charges flow and different forms of energy move within molecules and across molecular boundaries. The most demanding experiments would identify specific atoms and track their correlated electronic states, but the facilities don’t exist yet. Berkeley Lab scientists are using powerful lasers to devise future light sources that can do the job.

Beams to Order from Table-Top Accelerators

Laser plasma accelerators could create powerful electron beams within a fraction of the space required by conventional accelerators and light sources – and at a fraction of the cost. But fulfilling the promise of “table-top accelerators” requires the ability to tune stable, high-quality beams through a range of energies. Berkeley Lab scientists have demonstrated a two-stage, tunable laser plasma accelerator that meets the goal.

Putting a spin on light and atoms

Some of the most sensitive devices for detecting magnetic fields use light to put a spin on atoms and then measure the spin orientation. Now a team from Berkeley Lab, UC Berkeley, and the Vavilov State Optical Institute in Russia has achieved a remarkable technical advance with this kind of magnetometer, an advance that also has potential for improving atomic clocks, quantum memory devices, and a range of other scientific gadgets that depend on measuring spinning atoms with light.

For the First Time Ever, Scientists Watch an Atom’s Electrons Moving in Real Time

Using pulses of laser light measuring mere quintillionths of a second, an international team of scientists has probed the motion of an atom’s outermost electrons in real time. Their methods promise a broad new way to examine how atoms in physical, biological, and chemical systems bond with other atoms to form molecules or crystal structures, and how these bonds break and reform during chemical reactions.

Testing the Best-Yet Theory of Nature

With a confidence level of 100 billion to one, the most sensitive test yet shows that the spin-statistics theorem, one of the pillars of modern physics, really works: bosons and fermions are different.

Catching Electrons in the Act

Understanding how to create artificial photosynthesis, or tough, flexible high-temperature superconductors, or better solar cells, or a myriad other advances, will only be possible when we have the ability to image electrons by freezing time within a few quintillionths of a second. A leader in attosecond science tells how it’s done.