Low temperature Definition and 25 Threads

Hello! In many precision experiment, especially those overlapping with quantum computing techniques, such as trapping a few ions in a Paul trap, they use cryogenic systems (around 1K). I am not totally sure I fully understand the advantage of that, compared to room temperature. For example, a...

I find that $$U=\int Z \epsilon D(\epsilon) e^{-\epsilon β}d\epsilon=\frac{gV}{(2\pi)^3}\int Z \frac{(\hbar)^2k^2}{2m}k^2 (4\pi)e^{-β\frac{(\hbar)^2k^2}{2m}}dk$$ where g=2s+1=2, $$Z=e^{βµ}$$ and $$D(\epsilon)=\frac{gV}{(2\pi)^3}k^2 4\pi$$ for the density of states From here, I can use $$c_v...

Hello, i am trying to design a dewar for experiments at very low temperature. Unfortunately i do not know how to calculate the wall thickness. I can calculate the heat flow through the wall, but i do not know what to do further. Do someone know how to calcualte the thickness of the wall for a...

I want to learn the density matrix renormalization group (DMRG) method in traditional formalism (not MPS). While there are many good introductory level articles available for bosonic (and spin) systems, I have not encountered any introductory level article which deals with fermionic systems i.e...

Is it theoretically possible to cool a macroscopic crystal (for example NaCl 1×1×1 cm) to an extremely low temperature, like 1 nK? Will it retain its microscopic structure? Why? Does it have anything to do with zero point energy (I mean something like the lowest energy level of a quantum...

Suppose, there are two cylinders of compressed gas, say air. Both are at same temperature and pressure and the amount too is same. Now, contents of both are released but in a different way. One has been released directly and the other has been released through compressed air turbine having a...

Homework Statement The specific heat capacity of a metal at low temperature (T) is given as ##C_p = 32\left({\dfrac{T}{400}}\right)^3## (kJK-1kg-1). A 100g vessel of this metal is to be cooled from 20 K to 4 K by a special refrigerator operating at room temperature (27°C). The amount of work...

domainwhale submitted a new PF Insights post High Temperature Low Temperature Duality for the Ising Model on an Infinite Regular Tree Continue reading the Original PF Insights Post.

I know that an atom can become excited in one of two ways: by absorbing some energy from a source of electromagnetic radiation or by colliding with some other particle—another atom, for example, but my question is about the second part. So I want to know how and in what conditions (pressure...

And does rubidium ignite spontaneity in air...in powder phase or small piece of metal.

Could temperatures at a fraction of a kelvin be dangerous? We have only naturally observed temperatures of 1k But in a lab they did 100pk

I'm looking for chip carriers and sockets that will work well down to 4 K. Most aren't rated below -70 C, but I know in the past I've seen sets used down to 1.6 K. (Wish I could remember what they were!) Does anyone have specific recommendations? Or general advice, plastic vs ceramic, etc...

Dear all, In classical molecular dynamics simulation initial velocities are generated using the so called Maxwell distribution. At low temperature it's no longer effective, so I'm wandering whether there is a similar way to generate velocities at low temperature taking into account quantum...

Hi What could be the band diagram of pn-junction diode at very low temperature where dopant ionzation is completely frozen out? Would it still be like the band diagram at room temperature?

Hi Please remember that I'm not asking you for a diagnosis. My hands and feet are generally at low temperature than the overall temperature even when I'm wearing gloves or socks, or when in bed. Otherwise, I'm a healthy person. What could be the reason for this? Does genetics have anything...

Low Temperature Diesel Fuel (urgent) I'm having a problem with diesel fuel at the moment and would greatly appreciate insight into the subject. I'm currently stranded in Colorado where it's somewhere like -10 degrees (F) and our diesel truck isn't starting. I've narrowed down the problem to...

Are elements able to form a wider variety of molecules at lower temperatures vs say 20oC?

I need a LCC for low temperature measurement down to 10K or at least 77K. but I couldn't find any LCC capable of operating at that low temp. most commercially available LLC can only operate -70C. how you guys find a LCC operating below 77K? is it custom made?

Homework Statement (a) The formula for the multiplicity of an Einstein solid in the “high-temperature” limit, q >> N, was derived in one of the lectures. Use the same methods to show that the multiplicity of an Einstein solid in the “low-temperature” limit, q << N, is Ω(N,q)=(eN/q)^q...

Homework Statement - Is it possible to heat up water from 50 °C to 100 °C with saturated steam of 30 °C? - If my hand is at 37 °C, is this 30 °C steam hot or cold when I touch it? Homework Equations Steam tables. The Attempt at a Solution I'm a bit confused here because there...

Hi, This may seem basic bit but it is causing me a little confusion, any help would be appreseated. In theories such as Debye / Einstein it is stated that it this is true for low temperatures, coudl someone tell me what sort of temerautres they acutally mean by this? do they mean low as in...

I'm trying to derive a low temperature series expansion for the chemical potential of a weakly interacting Fermi gas. The starting point is, of course, the Fermi-Dirac distribution function (p is the particle momentum): f(p) = \frac{1}{e^{\beta(\epsilon(p) - \mu)}+1} , where, in the...

I need to do some head loss calculations for pumping diesel fuel or No. 2 fuel oil from a storage tank to an emergency generator. I see in many places that diesel fuel is specified to have kinematic viscosities of 1.3 to 4.1 cSt at 40C. However, under worst case scenarios, this fuel is likely...

A low temperature flame that melts carbon?? I saw this on television the other day. I have no idea how it works. It sound promising but so have a lot of other things in the past. There is a clickable news video in the link. http://freeenergynews.com/Directory/RhodesGas/index.html

I'm sure most of you have heard of the Einstein Referigeration Cycle . For those who have not I've listed the references for further reading.. http://www.me.gatech.edu/energy/pubs/SLA_2.pdf ok 342 K is about 156 F ,for anyone with an attic , it seems to me that this is the perfect solution to...