[HN Gopher] Thermal transistors handle heat with no moving parts
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       Thermal transistors handle heat with no moving parts
        
       Author : Turing_Machine
       Score  : 5 points
       Date   : 2023-11-14 07:00 UTC (16 hours ago)
        
 (HTM) web link (spectrum.ieee.org)
 (TXT) w3m dump (spectrum.ieee.org)
        
       | calamari4065 wrote:
       | Title is very unclear, but it looks like they're modulating
       | thermal _conductivity_ with an electric field. It 's definitely
       | not a peltier junction as I thought at first.
       | 
       | Seems like this is actually a novel mechanism. Very interesting,
       | I wonder what applications it will find? Cooling of CPUs seems
       | like a bad use case, but I'm sure someone will find a very
       | interesting application
        
         | dragontamer wrote:
         | I agree. Cooling of CPUs is awful use of this tech. Why would
         | anyone turn down thermal conductivity? Just always be sucking
         | heat out.
         | 
         | --------
         | 
         | The most obvious application would be electrically controlled
         | insulators.
         | 
         | If it's winter or summer, insulate the house.
         | 
         | But if outdoors is 72F (or 21C or another ideal temperature),
         | let the ideal temperature into the house.
         | 
         | Temperature controlled crystal oscillators are another
         | application IMO. Applications where we have a 'target
         | temperature', and easy access to differing temperatures (ex
         | inside the oven vs outside the oven vs the heat from a heater)
        
       | adrian_b wrote:
       | Free research paper:
       | 
       | https://www.researchgate.net/publication/375278656_Electrica...
        
       | westurner wrote:
       | "Test Processor With New Thermal Transistors Cools Chip Without
       | Moving Parts" https://www.tomshardware.com/news/test-processor-
       | with-new-th... :
       | 
       | > _Compared to normal cooling methods, the experimental
       | transistors were 13 times better._
       | 
       | "Electrically gated molecular thermal switch" (2023)
       | https://www.science.org/doi/10.1126/science.abo4297 :
       | 
       | > Abstract: _Controlling heat flow is a key challenge for
       | applications ranging from thermal management in electronics to
       | energy systems, industrial processing, and thermal therapy.
       | However, progress has generally been limited by slow response
       | times and low tunability in thermal conductance. In this work, we
       | demonstrate an electronically gated solid-state thermal switch
       | using self-assembled molecular junctions to achieve excellent
       | performance at room temperature. In this three-terminal device,
       | heat flow is continuously and reversibly modulated by an electric
       | field through carefully controlled chemical bonding and charge
       | distributions within the molecular interface. The devices have
       | ultrahigh switching speeds above 1 megahertz, have on /off ratios
       | in thermal conductance greater than 1300%, and can be switched
       | more than 1 million times. We anticipate that these advances will
       | generate opportunities in molecular engineering for thermal
       | management systems and thermal circuit design._
        
         | rcxdude wrote:
         | >Can switch at 1MHz
         | 
         | >can be switched "more than 1 million times"
         | 
         | Seems like longevity is a potential issue. Definitely could be
         | useful for a few applications (especially temperature control),
         | though I'm not really sure about a pure cooling application.
        
           | westurner wrote:
           | Would there be any returns to pairing this approach with
           | recent advances in laser cooling (and integrated photonics)?
        
       | hamilyon2 wrote:
       | It would be very handy technology in thermal batteries and
       | combined industrial processes which make use of waste heat.
       | 
       | Of course, you can use other ways to archive the same, but there
       | is something neat in solid-state zero moving parts approach.
        
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       (page generated 2023-11-14 23:01 UTC)