Internet is a funny thing. I started searching for some research paper but I ended up with a totally unrelated news feature from Nature 1, which ended up as an interesting read. It is about two Japanese crystal growers from Japan : Kenji Watanabe2 and Takashi Taniguchi 3 who work at National Institute of Materials Science (NIMS) in Tsukuba. They have come into the limelight for their outstanding skills of growing high quality crystals of hexagonal boron nitride or more commonly called as hBN in the research community. The news article gives a very nice overview of how they go about growing their crystals with an element of human touch 1 :
“The two researchers have contrasting styles. Taniguchi is known for his parties, blasts the music of Queen through the lab as he runs the press late at night and, even at the age of 60, still plays soccer with his colleagues at lunchtime. Watanabe, three years younger, is soft-spoken, detail-oriented and prefers tennis. But the scientists worked well together and published their first paper on cBN crystals in 2002.”
In scientific research, an important aspect of lab-based experiments is that it critically depends on the quality of the sample that one is interrogating, and more so in research on condensed matter, where quality of the material is paramount. After the emergence of graphene as a remarkable 2D material 4, various researchers across the globe (including IISER-Pune) have been intensely studying graphene and other 2D materials. In order to probe graphene in the lab, first you need to place the one atom thick material on a substrate. Generally, silicon (with or without silicon oxide) is used for this purpose. The electronic mobility of graphene, which is to be maximized for its magic work, critically depends on the quality of the substrate (and superstrate) on which it is placed on, and hBN is the best choice for maximum mobility. This is where quality of hBN comes into picture, and Watanabe and Taniguchi are considered the masters of growing high purity hBN crystals, exclusively for this purpose, as the news feature highlights 1. Of course, hBN is not limited to be just a substrate for graphene based nano-electronic devices. It has also emerged as an interesting nanophotonic material, which can potentially function as a hyper lens. All these applications critically depend on the quality of the sample one can produce, and hence, growth of high quality crystal is so important.
At IISER-Pune, right in front of my lab is the lab of my colleague – Surjeet Singh5. In his lab, they grow some fascinating crystals of quantum magnets, superconductors etc. Furthermore, many of my other colleagues, including chemists and biologists, grow and study crystals made of inorganic, organic and biological materials. I have to mention that, in India, there are many researchers across the country who are excellent crystal-growers. In fact, India has a rich history in crystal growth research ( for example: GN Ramachandran school 6), and I hope this legacy will continue with the support of academia and funding agencies. After all, high quality materials need high quality skills to grow and characterize them, and I have repeatedly heard that crystal growth is as much as an art as it is a science.
Speaking of science and art, Nobel prizes for 2020 has been announced. Great to see a good representation of women among the laureates this year. It is befitting to end this blog with a poem7 by Louise Glück (the literature laureate of 2020):
October (section I) by Louise Glück
Is it winter again, is it cold again,
didn’t Frank just slip on the ice,
didn’t he heal, weren’t the spring seeds planted
didn’t the night end,
didn’t the melting ice
flood the narrow gutters
wasn’t my body
rescued, wasn’t it safe
didn’t the scar form, invisible
above the injury
terror and cold,
didn’t they just end, wasn’t the back garden
harrowed and planted—
I remember how the earth felt, red and dense,
in stiff rows, weren’t the seeds planted,
didn’t vines climb the south wall
I can’t hear your voice
for the wind’s cries, whistling over the bare ground
I no longer care
what sound it makes
when was I silenced, when did it first seem
pointless to describe that sound
what it sounds like can’t change what it is—
didn’t the night end, wasn’t the earth
safe when it was planted
didn’t we plant the seeds,
weren’t we necessary to the earth,
the vines, were they harvested?
References :
1. Zastrow M. Meet the crystal growers who sparked a revolution in graphene electronics. Nature. 2019;572(7770):429-432. https://www.nature.com/articles/d41586-019-02472-0
2. WATANABE, Kenji | SAMURAI – National institute for Materials Science. WATANABE, Kenji | SAMURAI – National Institute for Materials Science. Accessed October 9, 2020. https://samurai.nims.go.jp/profiles/watanabe_kenji_aml
3. TANIGUCHI, Takashi | SAMURAI – National institute for Materials Science. TANIGUCHI, Takashi | SAMURAI – National Institute for Materials Science. Accessed October 9, 2020. https://samurai.nims.go.jp/profiles/taniguchi_takashi
4. The Nobel Prize in Physics 2010. NobelPrize.org. Accessed October 9, 2020. https://www.nobelprize.org/prizes/physics/2010/press-release/
5. Surjeet Singh. Accessed October 9, 2020. http://www.iiserpune.ac.in/~surjeet.singh/
6. G. N. Ramachandran. In: Wikipedia. ; 2020. Accessed October 9, 2020. https://en.wikipedia.org/w/index.php?title=G._N._Ramachandran&oldid=976314830
7. Poets A of A. October (section I) by Louise Glück – Poems | Academy of American Poets. Accessed October 9, 2020. https://poets.org/poem/october-section-i
Scatterings 