Physicists study coldest objects in universe
Nov. 27, 2013 In a new study published today in the Institute of Physics and German Physical Society's New Journal of Physics, a group of researchers from the UK and Australia have come up with a new way of measuring BECs by using a filter to cancel out the damage caused by the streams of light that are typically used to measure them.
Share This:
Not only can the filter create a best estimate of the state of BECs by removing "noise" from the measurements, it can also use these measurements to actively feedback to the BECs and remove some of the heating based on what has already been observed.
It is hoped that once this theory is realized experimentally, researchers will be able to gather much more information about BECs and extend their use in fundamental science, such as in atom lasers to precisely measure gravity and as models to study the emission of Hawking radiation from black holes.
In the future, they may also be used by the military to detect submarines, underground bunkers and threats, and to also see through stealth technology.
Lead author of the study Michael Hush, from the University of Nottingham, said: "It's like trying to check if your refrigerator is still working but not wanting to let cold air out by opening the door.
"The smallest amount of heat can destroy a BEC and many of even the most up-to-date imaging devices end up destroying the BEC after a single image. Experimentalists have demonstrated that a BEC can be imaged non-destructively for a limited amount of time, but our work will allow them to be imaged for much, much longer -- potentially indefinitely."
BECs are a cluster of atoms that are cooled until they are only 100 nano-Kelvin above absolute zero. At this temperature, the atoms lose their individual identity and behave as one macroscopic entity, almost like a superatom.
Because BECs are extremely cold, they have very little "noise" associated with them, so they are ideal for investigating physics that involves atoms -- such as probing atomic structure -- because they will exhibit very little interference.
The best way of measuring a BEC is to use off-resonant light, which tends to bounce off the atoms instead of being absorbed and thrown back out -- this happens when resonant light is used. Off-resonant light has a very different wavelength to the one that would naturally be absorbed and emitted by the atoms, so it doesn't disturb the BEC as much as resonant light and makes it much easier to measure.
Off-resonant light can cause some spontaneous-emission, however, which induces heating and can destroy a BEC, so the researchers developed a filter and feedback to control this heating effect, resulting in a net cooling of the BEC.
Hush continued: "We've essentially created a window to look into the world's coldest fridge. By peering through this window, we hope that scientists can potentially view previously inaccessible phenomena related to BECs and begin to realise their potential applications."
Welcome to SUV System Ltd!
SUV System Ltd is ISO 90012008 Certified electronics distributor with 10 years of experiences.
We have built up long term business relationship with about many companies which are stockers and authorized agents. we have a steady and reliable supply to meet customer's demands to the greatest extent .Confidently, we are able to lower your cost and support your business with our years of professional service.
SUV System Ltd is Electronic Components Distributor Supplies,Find Quality Electronic Components Supplies Products IC(Integrated Circuits),Connectors,Capacitor,Resistors,Diodes,Transistors,LED at Suvsystem.com. Sourcing Other Energy, Environment, Excess Inventory Products from Manufacturers and Suppliers at Suvsystem.com
Electronic Components distributor:http://www.suvsystem.com
Connectors Distributor:http://www.suvsystem.com/l/Connectors-1.html
IC Distributor:http://www.suvsystem.com/l/IC(Integrated-Circuits)-1.html
LED Distributor:http://www.suvsystem.com/l/LED-1.html
Capacitor Distributor:http://www.suvsystem.com/l/Capacitor-1.html
Transistor Distributor:http://www.suvsystem.com/l/Transistors-1.html
Resistor Distributor:http://www.suvsystem.com/l/Resistors-1.html
Diode Distributor:http://www.suvsystem.com/l/Diodes-1.html
SUV System Ltd insists on the managing faith ofsincereness,speciality,foresight, win-win,so we build up stable-relationship customers located all over the world, including the States, Europe, Argentina, UAE, Malaysia, Australia,and India etc
we are focus on the following fields,and hope we can help you.
TOSHIBA Diodes Military IC AD IC About US MOTOROLA IC Current Sensors Resistors Xilinx IC NEC Diodes VISHAY IC LITTELFUSE Diodes Infineon Technologies Transistors NEC Transistors components INFLNEON Diodes Transistors Freescale Fleld Effect Transistors NS IC DIODES Transistors Thin Film Resistors Freescale Semiconductor Chip Inductors Connectors Metal Can Packages Transistors chip Filter saws Chip Ferrite Beads Resistors IDT IC BB IC Bipolar Transistors PANASONIC Vishay resistors Fairchild Semiconductor Transistors Schottky Diodes High Precision Resistors Resistor Arrays Digital Transistors Kingbrigt LED ON Diodes LED part IC(Integrated Circuits)
http://www.suvsystem.com/a/7455.aspx
No comments:
Post a Comment