How many states does matter exist in? If you are like us, your answer will be three; solid, liquid, and gaseous. However, a team of scientists has discovered a new state of matter that can be created by bombarding it with an ultra-fast burst of light. The state mentioned above is stable at room temperature by frustrating the material’s natural tendency of going back to its ground state.
A team of scientists at Penn State, Argonne National Laboratory, and others have come up with a new and stable of the matter by making use of controlled pulses of laser light. Venkatraman Gopalan, the Penn State team leader and professor of materials science, said, ‘We are looking for hidden states of matter by taking the matter out of its comfortable state, which we call the ground state. We do this by exciting the electrons into a higher state using a photon, and then watching as the material falls back to its normal state. The idea is that in the excited state, or a state it passes through for the blink of an eye on the way to the ground state, we will find properties that we would desire to have, such as new forms of polar, magnetic and electronic states.’
This wonderful feat was accomplished by making use of a two-stage laser. The first laser was used for the sake of exciting the electrons into a higher state whereas the second laser was used to obtain the data about the material’s state. Typically these states of matter are temporary – they tend to exist for an only limited time, that too a fraction of a second, before the material hurries back to its ground state. The team wanted to exploit the properties of the material in any of these states, for that to happen its tendency to return to the ground state needed to be fixed.
The researchers used a complex 3D material that was created by alternating between layers of lead titanate and strontium titanate for frustrating the materials’ natural tendency of going back to their ground state. This enabled the team to keep the materials stable in the new state at room temperature for over a year.
A research team from Argonne National Laboratory said, ‘For the first time, we observed that a single ultrafast laser pulse irradiation of artificially layered polar material could induce long-range structural perfection when starting from the relative disorder. This experimental demonstration has already stimulated theoretical developments and has important implications toward the future realization of artificial nanomaterials that are not achievable by traditional fabrication.’
The research has been published in the journal Nature Materials.