The the study of Rydberg atoms/matter/cristals is a large new field in physics. So there is uncertainty in its characterization.
Here is a reference regarding Rydberg atom/matter life expectancy. For your converence, I highlighted the lifetime values. Reference: http://www.enotes.com/topic/Rydberg_matter *Lifetime* Schematic of an effective potential within a Wigner-Seitz cell<http://www.enotes.com/topic/Wigner-Seitz_cell>of a Rydberg matter made of excited (n=10) Cs atoms. [27]<http://www.enotes.com/topic/Rydberg_matter#cite_note-A._Manykin.2C_M._I_1992_P_75.2C_602-26> [28]<http://www.enotes.com/topic/Rydberg_matter#cite_note-A._Manykin.2C_1994_P_78-27> Circular Rydberg states of atoms are extremely long-lived against deexcitation by emission of radiation. The so called radiative lifetime of a circular Rydberg state in *n = 100 is approximately 1 second*. This means that it decays with a characteristic lifetime of *1 second*.[29]<http://www.enotes.com/topic/Rydberg_matter#cite_note-28>The lifetime averaged over the angular momentum quantum numbers is *0.18 s at n = 40 and 17 s for n = 100*.[30]<http://www.enotes.com/topic/Rydberg_matter#cite_note-29>The main reasons for such long lifetimes of atoms with excitation energy of several eV are the lack of spatial overlap between the excited circular orbital and low orbitals close to the atom, and the forbidden nature of transitions from high orbitals to low orbitals since the strong selection rule Δ*l* = -1 is operative in a dipole transition. Similar effects exist in the condensed Rydberg matter: significantly increased lack of orbital spatial overlap and angular momentum conservation as described make the lifetime of Rydberg matter long. In addition, quantum mechanical properties of the system, e.g. exchange-correlation effects, create an energy barrier (see figure) which further prevents the deexcitation of the valence electrons in the matter since the electrons have to tunnel through the barrier to the low states.[25]<http://www.enotes.com/topic/Rydberg_matter#cite_note-E.A._Manykin.2C_M.I._Ojovan_P_57-24>This means that the valence electrons are distributed extremely non-uniformly in the Rydberg matter causing a significant delay in the decay of excitations compared to non-interacting excited atoms. For example, the half-life of *Rydberg matter made of Cs atoms with a relatively low level of excitation at n = 12 is calculated to be as long as 17 s.[27]<http://www.enotes.com/topic/Rydberg_matter#cite_note-A._Manykin.2C_M._I_1992_P_75.2C_602-26> * Both the life-time and also the stability of Rydberg matter against impurity recombination increase rapidly with the quantum-mechanical level of excitation.[28]<http://www.enotes.com/topic/Rydberg_matter#cite_note-A._Manykin.2C_1994_P_78-27> *An extrapolation to n = 80 gives a lifetime close to the presently accepted age of the Universe.[31]<http://www.enotes.com/topic/Rydberg_matter#cite_note-L._Holmlid_P_100-30> * ** The reasons for the long lifetime and high stability of Rydberg matter against ionization are still debated in some parts of the physics community (verbatim), especially in the field studying ultracold plasmas. This is at least partly due to a lack of methods to observe Rydberg matter and Rydberg matter clusters in such experiments. As discussed in the literature,[32]<http://www.enotes.com/topic/Rydberg_matter#cite_note-L._Holmlid_2002-31>several experimental problems preventing the formation of Rydberg matter in the typical cold plasma setups have not been solved. *Experimental results using the published methods of Rydberg matter formation show lifetimes up to hours in the laboratory.[33]<http://www.enotes.com/topic/Rydberg_matter#cite_note-L._Holmlid_2005-32> [34]<http://www.enotes.com/topic/Rydberg_matter#cite_note-L._Holmlid_1992-33>Since Rydberg matter clusters can be maintained in their excited state by thermal radiation, Rydberg matter can exist for days in the experiments.* The kind of Rydberg matter this is refereing to is 2 dinentional Rydberg matter. It is formed into long tubes of up to and exceeding thousands of atoms. The is another type of Rydberg matter called Rydberg crystals. This is a three dementional Rydberg matter. A discription of these states of matter can be found in this reference: http://arxiv.org/pdf/1103.2096v2.pdf *Adiabatic Formation of Rydberg Crystals with Chirped Laser Pulses* The 3D crystals are amazing stuff. They look like a layered buckeyball with a structure like a nuclear shell. See the reference. There is no mention in the reference to how long the 3D variety will last but their size in terms of atom count can be huge. They only evaporate 1 atom at a time so the life expectancy will be very large for a big and energetic crystal. They have a lattice just like a metal. When coherent, the 3D Rydberg crystal being a super-atom thousands of atoms strong must pump out a huge coherent dipole moment. On Sun, Feb 12, 2012 at 4:01 PM, <[email protected]> wrote: > In reply to Axil Axil's message of Sat, 11 Feb 2012 01:17:08 -0500: > Hi, > [snip] > >There is strength in numbers, especially if large numbers of Rydberg atoms > >are coherent. This tendency for Rydberg atoms to sync up will make them > >very long lived because there will be no interfering wave patterns to > >disturb the coherent ensemble. > > > > > >See: > >Viewpoint: Rydberg Atoms Jump in Bunches > > > >http://physics.aps.org/articles/v5/5 > > Quote: > "Most of these schemes rely on the long radiative lifetime of highly > excited > atoms and therefore can typically operate no longer than a few > microseconds. " > > Unless I have misunderstood this, the implication is that Rydberg atoms > are only > stable on the order of microseconds before decaying. > > > > > > > > > > >On Fri, Feb 10, 2012 at 3:38 PM, <[email protected]> wrote: > > > >> In reply to Axil Axil's message of Fri, 10 Feb 2012 12:14:51 -0500: > >> Hi, > >> [snip] > >> >If not absorbed into the micro-powder, these large and excited > molecules > >> of > >> >all types will steal more Rydberg atoms from the envelope and grow even > >> >bigger. > >> > >> Normal Rydberg atoms are unstable to spontaneous decay to normal atoms > (if > >> I'm > >> not mistaken). > >> > >> IRH OTOH needs to find keV/atom to return to "normal". > >> > >> Regards, > >> > >> Robin van Spaandonk > >> > >> http://rvanspaa.freehostia.com/project.html > >> > >> > Regards, > > Robin van Spaandonk > > http://rvanspaa.freehostia.com/project.html > >
