䊉䊷䊃㩷㊄ዻ᳓⚛ൻ‛↪੤ᵹ⏛᧤⸘䈱᭴▽䈫䈠䈱ᕈ⢻⹏ଔ㩷㩷⿒ਣᖗ჻‫ޔ‬ጟ㦮࿻␭‫ޔ‬ේ ᱜᙗ‫᧻ޔ‬ጊ᡽ᄦንጊᄢቇ᳓⚛ห૏૕⑼ቇ⎇ⓥ࠮ࡦ࠲࡯‫ޥ‬930-8555 ንጊᏒ੖⑔ 3190㪚㫆㫅㫊㫋㫉㫌㪺㫋㫀㫆㫅㩷㫆㪽㩷㪘㫃㫋㪼㫉㫅㪸㫋㫀㫅㪾㪄㪚㫌㫉㫉㪼㫅㫋㩷㪤㪸㪾㫅㪼㫋㫆㫄㪼㫋㪼㫉㩷㪽㫆㫉㩷㪤㪼㫋㪸㫃㩷㪟㫐㪻㫉㫀㪻㪼㩷 㩷㪸㫅㪻㩷㪠㫋㫊㩷㪧㪼㫉㪽㫆㫉㫄㪸㫅㪺㪼㩷㪫㪼㫊㫋㫊㩷㩷

Satoshi Akamaru, Keisuke Okazaki, Masanori Hara, and Masao Matsuyama
Hydrogen Isotope Research Center, University of Toyama, Gofuku 3190, Toyama
930-8555, Japan(Received November 21, 2011; accepted March 9, 2012)
Abstract
An alternating-current magnetometer was assembled to measure the magnetic susceptibility ofmetal hydride in hydrogen atmosphere, and its performance tests were carried out.

Themagnetometer was designed to be integrated into the conventional pressure-composition-temperature(PCT) measurement system without any reconstruction.

Calibration of the magnetometer wasperformed using a paramagnetic Gd2O3 powder, and it gave a linear relationship between the output
signal and the magnetic moment of Gd2O3 powder. The magnetic susceptibility of PdHx (0 ≤ x ≤0.7) was measured simultaneously with the PCT curve. The magnetic susceptibility of Pd hydridedecreased with increasing hydrogen concentration in Pd and finally reached zero at the hydrogenconcentration above 0.65. The behavior of magnetic susceptibility and PCT curves quantitatively
agreed with the previously reported values.
1. ✜⸒
 ㊄ዻ᳓⚛ൻ‛ߪ᳓⚛⾂⬿᧚ᢱߣߒߡߩᔕ↪߇ᦼᓙߐࠇߡ߅ࠅ‫ޔ‬ᄙ⒳ᄙ᭽ߥ᧚ᢱ㐿⊒෸߮ߘߩ᳓⚛ๆ෼᡼಴․ᕈߦ㑐ߔࠆၮ␆⎇ⓥ߇⋓ࠎߦⴕࠊࠇߡ޿ࠆ‫৻ޕ‬ᣇߢ㊄ዻ᳓⚛ൻ‛ߩ‛ᕈ㧔㔚⏛᳇‫ޔ‬ᾲ‫ޔ‬శ‛ᕈߥߤ㧕ࠍ೑↪ߒߚᔕ↪⎇ⓥ[1,2]߽ⴕࠊࠇߡ޿ࠆ߇‫ޔ‬᳓⚛⾂⬿᧚ᢱ㑐ㅪߩ⎇ⓥߣᲧセߔࠆߣዋߥ޿‫ⷐߩߟ৻ߩߘޕ‬࿃ߣߒߡ‫ޔ‬㊄ዻ᳓⚛ൻ‛ߩ‛ᕈߦ㑐ߔࠆၮ␆⎇ⓥ߇ዋߥ޿ߎߣ߇⠨߃ࠄࠇࠆ‫ޕ‬
 ㊄ዻߩ⏛᳇․ᕈߪ‫ޔ‬ฎߊ߆ࠄ᭽‫ߥޘ‬Ꮏᬺ⵾ຠߦᔕ↪ߐࠇߡ޿ࠆ‫⃻ޔߚ߹ޕ‬࿷ߦ߅޿ߡ߽⏛ᕈ᧚ᢱߩᕈ⢻ะ਄ࠍ⋡ᜰߒߚ㐿⊒⎇ⓥ߇ⴕࠊࠇߡ޿ࠆ‫᧚ޕ‬ᢱ㐿⊒ߩⷰὐ߆ࠄ⷗ࠆߣ‫ޔ‬㊄ዻ᳓⚛ൻ‛ߪ⚿᥏ߩ᭴ㅧᄌൻࠍᒁ߈⿠ߎߔߎߣ߆ࠄ‫⏛ޔ‬᳇․ᕈߩ೙ᓮᚗ޿ߪᣂߚߥ․ᕈߩ
⊒⃻ߦ೑↪ߢ߈ࠆߣ⠨߃ࠄࠇࠆ‫ޔߒ߆ߒޕ‬㊄ዻ᳓⚛ൻ‛ߪ᳓⚛ๆ෼ߦࠃࠅᄙߊ߇ᓸ☳ൻߒ‫ޔ‬ᄢ᳇ਛߦขࠅ಴ߔ㓙ߦ⴫㕙㉄ൻߩᓇ㗀ࠍฃߌࠆߚ߼‫ޔ‬㊄ዻ᳓⚛ൻ‛ߦኻߔࠆ⏛᳇․ᕈߩᱜ
⏕ߥ᷹ቯ߇࿎㔍ߢ޽ߞߚ‫ޕ‬ ߘߎߢᧄႎ๔ߢߪ‫ޔ‬᳓⚛ๆ෼᡼಴․ᕈߩ⹏ଔߦ↪޿ࠄࠇߡ޿ࠆ‫ޔ‬࿶ജ-⚵ᚑ-᷷ᐲ․ᕈ
㧔PCT㧕᷹ቯⵝ⟎߆ࠄ㊄ዻ᳓⚛ൻ‛ࠍขࠅ಴ߔߎߣߥߊ‫ޔ‬᳓⚛ࠟࠬ㔓࿐᳇ਛߦߡ‫ޔ‬᳓⚛ൻ‛ߩ⏛᳇․ᕈࠍ᷹ቯߔࠆߚ߼‫ޔ‬PCT ᷹ቯⵝ⟎ߦኈᤃߦ⚵ߺㄟ߼ࠆ੤ᵹ⏛᧤⸘ߩ᭴▽ࠍⴕ޿‫ޔ‬ߘߩᕈ⢻⹏ଔࠍ Pd ☳ᧃࠍ↪޿ߡⴕߞߚ‫ޕ‬
2. ੤ᵹ⏛᧤⸘ߩේℂߣⵝ⟎ߩ᭴▽
2.1. ⶄ⚛⏛ൻ₸ ߪߓ߼ߦ੤ᵹ⏛႐ਅߢߩ⏛ൻ₸ߦߟ޿ߡ◲නߦ⺑᣿ߔࠆ[3]‫⏛ޕ‬႐ߩᣇะ߇๟ᦼ⊛ߦᄌൻߔࠆ੤ᵹ⏛႐ਅߦ⹜ᢱ߇޽ࠆ႐ว‫⹜ޔ‬ᢱߩ⏛ൻ₸ χ (m3/kg)ߪⶄ⚛⏛ൻ₸ χ̂ ߣߒߡએਅߩࠃ߁ߦ⸥ㅀߐࠇࠆ‫ޕ‬χˆ = χ ′ − jχ ′′…(1)ߎߎߢ‫ޔ‬j ߪ⯯ᢙන૏ࠍ⴫ߔ‫ ߦ⥸৻ޕ‬χ ′ ߪ⏛᳇ᔕ╵ߩ๟ᵄᢙଐሽᕈࠍ␜ߒ‫ ޔ‬χ ′′ ߪ⏛ᕈ૕ౝߩ౒㡆࡮✭๺⃻⽎ߦࠃࠆ⏛᳇ᔕ╵ߩㆃࠇࠍ␜ߒߡ޿ࠆ‫ ߪߢߎߎޔ߅ߥޕ‬SI න૏♽㧔E-B ኻᔕ㧕ࠍ↪޿ߡోߡߩᑼࠍ⸥ㅀߔࠆ‫ޕ‬੤ᵹ⏛႐ Ĥ (Am-1)ਅߢߩ⏛ൻ₸ χ̂ ‫⹜ޔ‬ᢱਛߩ⏛᧤ኒᐲ

B̂ (Wb/m2)‫ޔ‬෸߮⹜ᢱߩ⾰㊂⏛ൻ M̂ (Am2/kg)ߣߩ㑐ଥߪ㕒⏛႐ਅߢߩ㑐ଥߣᄌࠊࠄߕ‫ޔ‬Bˆ = µ 0 (1 + χˆ )Hˆ ‫ ޔ‬Mˆ = χˆHˆ…(2, 3)ߣߥࠆ‫ ޔߢߎߎޕ‬µ 0 ߪ⌀ⓨਛߩㅘ⏛₸ࠍ␜ߔ‫ޕ‬੤ᵹ⏛႐ Ĥ ߩⷺᝄേᢙࠍ ω (2π/sec)ߣߔࠆ
ߣ‫ ޔ‬Ĥ ෸߮ B̂ ߪએਅߩࠃ߁ߦ⸥ㅀߐࠇࠆ‫ޕ‬Hˆ = H 0 exp ω t…(4)Bˆ = B0 exp(ω t − δ )…(5)
H 0 ෸߮ B0 ߪߘࠇߙࠇߩᝄ᏷ߩᄢ߈ߐߢ޽ࠅ‫ ޔ‬t (sec)ߪᤨ㑆ߢ޽ࠆ‫ ޕ‬B̂ ߦ౉ߞߡ޿ࠆ δ ߪ‫ޔ‬H 0 ߆ࠄߩ૏⋧ߩㆃࠇࠍ␜ߔ‫ޕ‬਄⸥ߒߚࠃ߁ߦ‫ޔ‬૏⋧ߩㆃࠇߪ χ ′′ ߦ㑐ㅪߔࠆ㗄ߢ޽ࠅ‫ޔ‬ω ߇ዊߐߌࠇ߫ δ ߪ߶߷ 0 ߣߥࠆ‫⁁ߩߎࠅ߹ߟޕ‬ᴫਅߢߪ‫ ޔ‬χ ′ ߪ㕒⏛႐ਅߢߩ⏛ൻ₸ χ ߣ৻⥌ߔࠆߎߣ߇⍮ࠄࠇߡ޿ࠆ‫(ޕ‬2)-(5)ᑼࠍ↪޿ࠆߣ‫ ޔ‬χ ′ ෸߮ χ ′′ ߪએਅߩࠃ߁ߦ⸥ㅀߐࠇࠆ‫ޕ‬µ 0 (1 + χˆ ) =χ′ =Bˆ B0 exp(ω t − δ ) B0
B==exp(− δ ) = 0 (cos(− δ ) + j sin (− δ ))
ˆH 0 exp ω tH0H0HB0cos δ − 1µ0 H 0…(7)…(6)χ ′′ =B0sin δµ0 H 0…(8)ߟ߹ࠅ‫ ޔ‬χ ′ ෸߮ χ ′′ ߪ⹜ᢱਛߩ⏛᧤ኒᐲ B̂ ߩ੤ᵹ⏛႐ Ĥ ߣหߓ૏⋧ࠍᜬߟᚑಽߣ‫ޔ‬90o ߛߌ૏⋧ߩㆃࠇߚᚑಽࠍ᷹ቯߔࠆߎߣߢ᳞߼ࠆߎߣ߇ߢ߈ࠆ‫ޕ‬
2.2 ੤ᵹ⏛᧤⸘ߩේℂ੤ᵹ⏛᧤⸘ߢߪ‫ޔ‬੤ᵹ⏛႐ਅߢߩ⹜ᢱਛߩ⏛᧤ኒᐲߩᄌൻࠍ࠰࡟ࡁࠗ࠼ࠦࠗ࡞߳ߩ⺃ዉ⿠㔚ജߣߒߡᬌ಴ߔࠆ‫ߩߘޕ‬ේℂࠍએਅߦ⺑᣿ߔࠆ[4]‫ޕ‬੤ᵹ⏛႐⊒↢↪ߣߒߡ↪޿ࠆඨᓘ a‫ޔ‬㐳ߐ l‫✢ޔ‬Ꮞ߈ᢙ N1 ߩਛⓨߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 1㧔࡝ࠕࠢ࠲ࡦࠬ L1㧕ߦએਅߩ੤ᵹ㔚࿶ Vˆ1 ࠍශടߔࠆ‫ޕ‬Vˆ1 = V0 exp jωt…(9)V0 ߪ੤ᵹ㔚࿶ߩᝄ᏷ߢ޽ࠆ‫ ࡞ࠗࠦ࠼ࠗࡁ࡟࠰߈ߣߩߎޕ‬1 ߦᵹࠇࠆ㔚ᵹ Iˆ1 ߪ‫ޔ‬Vˆ V exp jω tIˆ1 = 1 = 0=Zˆ1 R1 + jω L1ૉߒ‫ ޔ‬θ1 = tan−1V0R + (ω L1 )2
12exp j (ω t − θ1 ) ‫ޔ‬ωL1R…(10)…(11)ߣߥࠆ‫ ޔߢߎߎޕ‬Ẑ1 ߪ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 1 ߩⶄ⚛ࠗࡦࡇ࡯࠳ࡦࠬ‫ޔ‬R1 ߪ࠰࡟ࡁࠗ࠼ࠦࠗ࡞1 ߩ㔚᳇ᛶ᛫ߢ޽ࠆ‫ߩߎޕ‬㔚ᵹ Iˆ ߦࠃࠅ‫ ࡞ࠗࠦ࠼ࠗࡁ࡟࠰ޔ‬1 ߩ┵߆ࠄ〒㔌 x ߩ႐ᚲߦ⊒↢ߔࠆ⏛႐ Ĥ1 ߪ‫ޔ‬ⓨߩࠦࠗ࡞ਛߩ⏛᧤ኒᐲ B̂1 ࠃࠅએਅߩࠃ߁ߦᦠߌࠆ‫ޕ‬Bˆ
N Iˆ xl−xHˆ 1 = 1 = 1  2−2 
2µ02l  a + x 2a + (l − x ) …(12)Nxl−xV0= 1−exp j (ωt − θ1 )222 
22l  a 2 + x 2a+(l−x)
R+(ωL)
1 1ߎߩ੤ᵹ⏛႐ߩਅߢ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 1 ߩਛᔃㇱ㧔x = l/2㧕ߦⶄ⚛⏛ൻ₸ χ̂1 ߩ⹜ᢱࠍኒߦߟ߼ߚ႐ว‫⹜ޔ‬ᢱਛߩ⏛᧤ኒᐲ Bˆ1in ߪએਅߩࠃ߁ߦᦠ߈⴫ߐࠇࠆ‫ޕ‬Bˆ1in = µ 0 (1 + χˆ1 )Hˆ 1= µ 0 (1 + χˆ1 )V0

N
22 4a + l

2

R1 + (ω L1 )22exp j (ω t − θ1 )…(13)ߎߩ⏛᧤ኒᐲߩᄌൻߦࠃࠅ‫ ࡞ࠗࠦ࠼ࠗࡁ࡟࠰ޔ‬1 ߦ㊀ߨߡᏎ޿ߚ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ߦߪએਅߩ⺃ዉ⿠㔚ജ Vˆ2 in ߇⊒↢ߔࠆ‫ޕ‬dBˆ
Vˆ2 in = − S2 1in
dt= (1 + χˆ1 exp(− jδ ))µ 0 NSω
2 4a 2 + l 2πexp j  ω t − θ1 − 222
R1 + (ω L1 )V0…(14)ߎߩᑼߪవ㗡ߩ᜝ᒐਛߩੑߟߩ㗄ߦಽߌࠄࠇ‫ޔ‬೨ߩ㗄ߪ੤ᵹ⏛႐߇⿠ߎߔ㧔⹜ᢱ߇ή޿႐วߩ㧕⺃ዉ⿠㔚ജ‫ޔ‬ᓟߩ㗄ߪ⹜ᢱਛߩ⏛᧤ኒᐲߩᄌൻߦ⿠࿃ߒߚ⺃ዉ⿠㔚ജߣߥߞߡ޿ࠆ‫ޕ‬ߎࠇࠃࠅ‫⹜ޔ‬ᢱࠍ⹣߼ߚ㓙ߩ⺃ዉ⿠㔚ജ߆ࠄ‫⹜ޔ‬ᢱ߇ή޿႐วߩ⺃ዉ⿠㔚ജࠍᒁߊߎߣߦࠃࠅ‫⹜ޔ‬ᢱߩⶄ⚛⏛ൻ₸ߩᄢ߈ߐ χ̂1 ෸߮૏⋧ߩߕࠇ δ 㧔ᚗ޿ߪ χ ′ ෸߮ χ ′′ 㧕ߦ㑐ߔࠆᖱႎࠍᓧࠆߎߣ߇ߢ߈ࠆ‫ޕ‬
2.3 ੤ᵹ⏛᧤⸘ߩ᭎ⷐ ᷹ቯⵝ⟎ߩ᭎⇛ࠍ࿑ 1 ߦ␜ߔ‫ޕ‬࿑ਛߩ⎕✢ߢ࿐߹ࠇߚㇱಽ߇‫੹ޔ‬࿁᭴▽ߒߚ੤ᵹ⏛᧤⸘ߢ޽ࠅ‫ߩઁߩߘޔ‬ㇱಽߪᣢሽߩ PCT ᷹ቯⵝ⟎ߢ޽ࠆ‫ޕ‬੤ᵹ⏛᧤⸘ࠍᣢሽߩ᳓⚛ๆ෼᡼಴᷹
ቯⵝ⟎ߦ⚵ߺㄟ߻㓙ߪ‫⹜ޔ‬ᢱ▤એᄖߪⵝ⟎ߩᡷㅧࠍᔅⷐߣߒߥ޿‫ޔߚ߹ޕ‬੤ᵹ⏛᧤⸘ߣ PCT᷹ቯⵝ⟎ߪ੕޿ߦ⁛┙ߦ૶↪น⢻ߢ޽ࠆ‫ޕ‬ ੤ᵹ⏛᧤⸘ߪ੤ᵹାภ⊒ାᯏ㧔DF1906, NF ࿁〝⸳⸘ࡉࡠ࠶ࠢ㧕෸߮ࡠ࠶ࠢࠗࡦࠕࡦࡊ
㧔Model 5210, SEIKO Instruments㧕‫ߡߒߘޔ‬ౝᓘ 8 mm‫ޔ‬ᄖᓘ 10 mm ߩ⍹⧷▤ߦᏎ޿ߚ 3 ߟߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ࠃࠅ᭴ᚑߐࠇࠆ‫ޕ‬࿑ 1 ਛߦ⸥タߒߚ੤ᵹ⏛᧤⸘ߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ߩ߁ߜ‫ޔ‬Ꮐ஥ߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 1 ߇੤ᵹ⏛႐⊒↢↪ߢ޽ࠅ‫ޔ‬ฝ஥ߩ 2 ߟߩ࠰࡟ࡁࠗ࠼ࠦࠗ
࡞ 2‫ޔ‬
3 ߇⹜ᢱߩ⺃ዉ⿠㔚ജ᷹ቯ↪ߢ޽ࠆ‫ޕ‬࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ߣ 3 ߪ‫ޔ‬੤ᵹ⏛႐⊒↢ᤨߦࠦࠗ࡞ߩਛ߇ⓨߩ⁁ᘒߢ߶߷หߓ಴ജ߇ᓧࠄࠇ‫ޔ‬ਔ⠪ߩ಴ജߩᏅಽ߇߶߷ 0 ߦߥࠆࠃ߁ߦᏎ߈ᢙࠍ⺞ᢛߒߡ޽ࠆ‫ࠅ߹ߟޕ‬⹜ᢱ᷹ቯᤨߪ‫ ޔ‬ᣇߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ߦ

TMP⹜ᢱࠍ㈩⟎ߒ‫ ߁߽ޔ‬ᣇߩⓨߩ࠰࡟ࡁࠗ࠼RPH2gasࠦࠗ࡞߆ࠄ⊒↢ߔࠆ಴ജࠍᏅߒᒁߊߎߣ

Coil 3ߢ‫⹜ޔ‬ᢱߩ⏛ൻ₸ߦ⿠࿃ߒߚ⺃ዉ⿠㔚ജߩߺࠍขࠅ಴ߔ‫ߒ߆ߒޕ‬ታ㓙ߦߪ‫ޔ‬ⓨߩ⁁ᘒ

Lock-in
Amplifierߢߩ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ෸߮ 3 ߩ಴ജߪቢోߦ৻⥌ߖߕ‫⚿ޔ‬ᨐߣߒߡਔ⠪ߩᏅಽߩ಴
ജࠍࡠ࠶ࠢࠗࡦࠕࡦࡊߢ᷹ቯߔࠆߣ‫৻ޔ‬ቯ

Coil 1

Coil 2
Pd powderߩ⺃ዉ⿠㔚ജ Vback ߇ᬌ಴ߐࠇࠆ‫ࠅ߹ߟޕ‬ታ㓙ߦ⹜ᢱࠍ᷹ቯߒߚ႐ว‫ࠗࠦ࠼ࠗࡁ࡟࠰ޔ‬࡞ 2 ߦ⹜ᢱࠍ⸳⟎ߒ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ߩ಴ജ߆ࠄ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 3 ߩ಴ജࠍᏅߒ

Fig. 1. Schematic view of alternating
current susceptometer and conventional PCT
measurement system.

ᒁ޿ߚ⺃ዉ⿠㔚ജ V2in ࠍ᷹ቯߔࠆߣ‫ޔ‬

V2 in = Vback + Vsample…(15)ߣߥࠆ‫ޔࠅ߹ߟޕ‬V2in ߪ⹜ᢱߦ⿠࿃ߒߚ⺃ዉ⿠㔚ജ Vsample ߦ Vback ߇ടࠊߞߚ୯ߣߥࠆ‫ߩߎޕ‬Vback ࠍขࠅ㒰ߊߚ߼‫ޔ‬V2in ࠍ᷹ቯߒߚᓟ‫⹜ޔ‬ᢱࠍ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 3 ߦ⒖േߒ‫ޔ‬V2in ࠍ᷹ቯߒߚ႐วߣหߓࠃ߁ߦ‫ ࡞ࠗࠦ࠼ࠗࡁ࡟࠰ޔ‬2 ߩ಴ജ߆ࠄ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 3 ߩ಴ജࠍᏅߒᒁ޿ߚ⺃ዉ⿠㔚ജ V3in ࠍ᷹ቯߔࠆ‫ޕ‬V3in = Vback − Vsample…(16)(15)ᑼ෸߮(16)ᑼࠃࠅ‫ޔ‬V2in ߆ࠄ V3in ࠍᒁ޿ߚ୯∆V ߪ Vsample ߩߺߩ಴ജߣߥࠆߎߣ߇ࠊ߆ࠆ‫ޕ‬ᧄ᷹ቯߢߪએ਄ߩᚻᴺࠍ↪޿ߡ∆V ࠍ᷹ቯߒߚ‫ߩߘޕ‬㓙‫⹜ޔ‬ᢱ૏⟎ߩ⒖േߪ࠰࡟ࡁࠗ࠼ࠦࠗ
࡞ో૕ࠍ⒖േߔࠆߎߣߦࠃࠅⴕߞߚ‫੹ޔߚ߹ޕ‬࿁⺃ዉ⿠㔚ജߩᬌ಴ߦ↪޿ࠆࡠ࠶ࠢࠗࡦࠕ
ࡦࡊߢߪ‫ޔ‬੤ᵹ㔚࿶ߩᝄ᏷෸߮ෳᾖାภ㧔ߎߎߢߪ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 1 ߦࠃࠅ⊒↢ߔࠆ੤ᵹ⏛႐㧕߆ࠄߩ૏⋧ߩߕࠇࠍหᤨߦ᷹ቯน⢻ߢ޽ࠅ‫ߩߎޔ‬ᯏ⢻ࠍ↪޿ߡ‫ ޔ‬χ ′ ߦᲧ଀ߔࠆෳᾖାภߣห૏⋧ߩ಴ജ∆Vx‫ ߮ࠃ߅ޔ‬χ ′′ ߦᲧ଀ߔࠆ 90O ㆃࠇߚ૏⋧ߩ಴ജ∆Vy ࠍ᳞߼ߚ‫ޕ‬2.4 ੤ᵹ⏛᧤⸘ߩᩞᱜ᷹ቯߒߚ⺃ዉ⿠㔚ജ߆ࠄ⏛ൻ₸߳ߩᄌ឵ߪ‫⏛߼੍ޔ‬ൻ₸߇ᣢ⍮ߢ޽ࠆᮡḰ⹜ᢱߦࠃࠅᓧࠄࠇࠆ⺃ዉ⿠㔚ജߣ⏛ൻ₸ߩ㑐ଥࠍ↪޿ߡ߅ߎߥߞߚ‫੹ޕ‬࿁ߪᮡḰ⹜ᢱߣߒߡ Gd2O3 ☳ᧃࠍ↪޿ߚ‫ޕ‬ᚲቯߩ㊀㊂ߩ Gd2O3 ☳ᧃࠍߟ߼ߚ㐳ߐ 10 mm ⒟ᐲߩ࠹ࡈࡠࡦ⵾ߩ╴ࠍ‫ޔ‬Gd2O3☳ᧃߩ㊀㊂ࠍᄌ߃ߡ 5 ⒳㘃૞ᚑߒ‫⺃ߩࠇߙࠇߘޔ‬ዉ⿠㔚ജࠍ᷹ቯߒߚ‫ޕ‬᷹ቯ଀ߣߒߡ Gd2O3☳ᧃ 45.4 mg ߩ᷹ቯᤨߩ⺃ዉ⿠㔚ജߩᄌൻࠍ࿑ 2 ߦ␜ߔ‫ޕ‬࿑ 2 ߦ␜ߒߚ⺃ዉ⿠㔚ജߪ࠰࡟ࡁ
ࠗ࠼ࠦࠗ࡞ 2 ߆ࠄ࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 3 ߩ಴ജࠍᏅߒᒁ޿ߚ୯ߢ޽ࠅ‫ࡦࠕࡦࠗࠢ࠶ࡠߦᦝޔ‬ࡊߦࠃࠅ੤ᵹ⏛႐ߣห૏⋧ߩ Vx‫ޔ‬෸߮૏⋧߇ 90O ㆃࠇߚ Vy ࠍಽ㔌ߒߡ᷹ቯߒߚ⚿ᨐߢ޽ࠆ‫ޕ‬߹ߚ‫ޔ‬࿑ 2 ߩԘߩ㗔ၞ߇࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ߦ⹜ᢱࠍ㈩⟎ߒߚ႐วߩ಴ജ㧔(15)ᑼߩ V2in ߦ⋧ᒰ㧕‫ޔ‬ԙߩ㗔ၞ߇࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 3 ߦ⹜ᢱࠍ㈩⟎ߒߚ႐วߩ಴ജ㧔(16)ᑼߩ V3in ߦ⋧ᒰ㧕ߢ޽ࠆ‫ޔࠅࠃࠇߎޕ‬Vback ߣߒߡ Vx ߢ-510 µV‫ޔ‬Vy ߢ 280 µV ⒟ᐲߩ಴ജ߇޽ࠆߎߣ߇ࠊ߆ࠆ‫ޕ‬ߎࠇ߇࠰࡟ࡁࠗ࠼ࠦࠗ࡞ 2 ෸߮ 3 ߩࠕࡦࡃ࡜ࡦࠬಽߩ಴ജߣߥࠆ‫⹜ޕ‬ᢱߩ⏛ൻ₸ߦኻᔕߔࠆ‫ޔ‬ԘߣԙߩᏅಽ∆V ߪ‫∆ޔ‬Vx ߢ 14.1 µV ಴ജߐࠇࠆߩߦኻߒߡ‫∆ޔ‬Vy ߢߪ߶ߣࠎߤ 0 ߣߥࠆ‫ޕ‬ߟ߹ࠅ‫੹ޔ‬࿁↪޿ߚ๟ᵄᢙߢߪ‫ޔ‬૏⋧ߩߕࠇߪ߶߷ 0 ߣߥࠅ‫ޔ‬Vx ࠃࠅ᳞߼ࠆ χ ′ ߩ୯ߪ㕒⏛႐ਅߢߩ⏛ൻ₸ χ ߦ߶߷৻⥌ߔࠆߣ޿߃ࠆ‫∆ߩߎޕ‬V ߣ Gd2O3 ߩ㊀㊂ߩ㑐ଥࠍ᷹ቯߒߚ⚿ᨐ
ࠍ࿑ 3 ߦ␜ߔ‫ޕ‬᷹ቯߪฦ㊀㊂ߢ 5 ࿁ⴕߞߚ‫⚿ߩߎޕ‬ᨐࠃࠅ‫∆ޔ‬Vx ߪ Gd2O3 ߩ㊀㊂ߦኻߒߡ⋥✢㑐ଥ‫∆ޔ‬Vy ߪో㗔ၞߢ߶߷ 0 ߢ޽ࠆߣࠊ߆ࠆ‫∆ޕ‬Vx ߩ⋥✢ࠍᦨዊੑਸ਼ᴺߦࠃࠅㄭૃߔࠆߎߣߢ‫ޔ‬࿑ 3 ਛߦ␜ߔᑼ߇ᓧࠄࠇߚ‫ޕ‬Gd2O3 ߩ⏛ൻ₸ߪቶ᷷ߢ 1.7410-6 m3/kg ߢ޽ࠆߎߣ߇
⍮ࠄࠇߡ߅ࠅ[5]‫ߩߎޔ‬୯ߣᦨዊੑਸ਼ᴺߦࠃࠅᓧࠄࠇߚ⋥✢ߩᑼ߆ࠄ‫ޔ‬ਅ⸥ߩ⺃ዉ⿠㔚ജ∆Vx(µV)ߣ⏛ൻ₸ χ (m3/kg)ߩ㑐ଥᑼࠍᓧߚ‫ޕ‬y = 0.10386 + 0.31292x , R= 0.99913

Gd O powder (45.4 mg)

16∆V-510280x-515

x_Gd2O3285output signal, ∆V-505

275
270-5200100200300400time, t / sec

500600Fig. 2. Typical measurement result ofin-phase and out-of-phase output voltage for45.4 mg Gd2O3 powder.

χ=Gd O powder

142143121210

1088664422000102030
Gd O weight, w
23Gd2O340/ mg

50Fig. 3. Gd2O3 weight dependence of outputsignal, ∆Vx and ∆Vy. The dashed line shows
the result by least squared fit to ∆Vx.

(∆Vx − 0.10386 ) × 1.74 × 10− 6 × 10.3129216/ µV290㽳y㽲

output voltage, V / µV

xoutput voltage, V / µV-500/ µV

f = 487 Hz, Vp-p = 10 V, 295 K

Y_Gd2O3

3

output signal, ∆V

2W…(17)ߎߎߢ‫ޔ‬W (mg)ߪ᷹ቯ⹜ᢱߩ㊀㊂ࠍ␜ߔ‫ޕ‬Pd ᳓⚛ൻ‛ߩ᷹ቯߦࠃࠅᓧࠄࠇߚ∆Vx ߪߎߩᑼࠍ↪޿ߡ⏛ൻ₸ߦᄌ឵ߒߚ‫ޔߚ߹ޕ‬ฦ㊀㊂ߢ᷹ቯߒߚ 5 ὐߩᮡḰ஍Ꮕࠍ᳞߼ࠆߣ‫ᦨޔ‬ᄢߢ
0.208 µV ߢ޽ߞߚ‫ޕ‬ᮡḰ஍Ꮕߩ 2 ୚ࠍಽ⸃⢻ߣߔࠆߣ‫ޔ‬Pd ᷹ቯᤨߢߩⵝ⟎ߩಽ⸃⢻ߪ਄ᑼ
ࠃࠅ 2.1710-9 m3/kg ߣ⷗Ⓧ߽ࠄࠇߚ‫ޕ‬
㧔㧡㧕Pd ᳓⚛ൻ‛ߩ᷹ቯ ᷹ቯ⹜ᢱߢ޽ࠆ Pd㧔99.9㧑‫ࠦ࡜࠾ޔ‬㧕ߪ‫ߦ⁁ᧃ☳ߢࠅߔ߿ࠢ࠶ࡒ࡜࠮ࠍߩ߽ߩ⁁᧼ޔ‬ടᎿߒߚ߽ߩࠍ↪޿ߚ‫ߩߘޕ‬ᓟ‫ޔ‬PCT ᷹ቯⵝ⟎ߦขࠅઃߌߚ⍹⧷࠮࡞ਛߦ‫ ⚂ޔ‬1 g ߩ☳ᧃ Pdࠍ޿ࠇ‫࡞࠮ޔ‬ਛࠍ 510-5 Pa એਅ߹ߢឃ᳇ߒߚ‫ߩߘޕ‬ᓟ‫ޔ‬ᵴᕈൻಣℂߣߒߡ 523 K ߢ 2 h ߩടᾲឃ᳇ࠍⴕ޿‫ޔ‬಄ළᓟߩ⁁ᘒࠍ᳓⚛Ớᐲ[H]/[Pd] = 0 ߣߒߚ‫ ࠄ߆ߎߎޕ‬Pd ߦ৻ቯ㊂ߩ H2ࠟࠬࠍዉ౉ߒ‫ޔ‬Pd ᳓⚛ൻ‛ߣ᳇⋧ߩ H2 ࠟࠬ߇ᐔⴧߦ㆐ߒߚߩߜߦ‫ޔ‬਄⸥ⵝ⟎ߦࠃࠅ Pd ᳓⚛ൻ‛ߩ⺃ዉ⿠㔚ജࠍ᷹ቯߒߚ‫ޔࠍࠇߎޕ‬ᐔⴧ࿶߇ 0.1 MPa ⒟ᐲߦߥࠆ߹ߢ➅ࠅ㄰ߒⴕߞߚ‫ޕ‬⺃ዉ⿠㔚ജߩ᷹ቯߪ‫ޔ‬295 ~ 300 K ߩቶ᷷ߦߡ‫ ࡞ࠗࠦ࠼ࠗࡁ࡟࠰ޔ‬1 ߦ๟ᵄᢙ 487 Hz‫ޔ‬੤ᵹᝄ᏷ Vp-p㧔ᦨᄢ୯ߣᦨዊ୯ߩᏅ㧕10 V ߩ੤ᵹ㔚࿶ࠍශടߔࠆߎߣߢⴕߞߚ‫ޕ‬
3. ታ㛎⚿ᨐ ࿑ 4 ߦ੤ᵹ⏛᧤⸘ࠍ↪޿ߡ᷹ቯߒߚ Pd ᳓⚛ൻ‛ߩ∆Vx ෸߮∆Vy ߩ᳓⚛Ớᐲଐሽᕈ‫ޔ‬෸߮ᐔⴧ࿶ߩ᳓⚛Ớᐲଐሽᕈࠍ␜ߔ‫ޕ‬Pd ߩᐔⴧ࿶ߪ[H]/[Pd] = 0.05 એ਄ 0.6 ᧂḩߢ߶߷৻ቯߩ୯ࠍ␜ߒ‫[ޔ‬H]/[Pd] > 0.6 ߢᕆỗߦჇടߒߚ‫ߩߎޕ‬௑ะߪㆊ෰ߦ᷹ቯߐࠇߚ⚿ᨐ[6]ߣࠃߊ৻⥌ߒߚ‫ޕ‬ᐔⴧ࿶ߣหᤨߦ᷹ቯߒߚ∆Vx ߅ࠃ߮∆Vy ߦߟ޿ߡߪ‫∆ޔ‬Vx ߪ᳓⚛Ớᐲ߇㜞ߊߥࠆߦᓥ޿න⺞ߦᷫዋߒ‫[ޔ‬H]/[Pd] = 0.65 ߢߪ߶߷ 0 ߦ೔㆐ߒߚ‫ࠇߘޔߚ߹ޕ‬એ਄ߩ᳓⚛Ớᐲߢߪ∆Vx ߪx10P50∆V1y-5-1000.1

0.2

0.3 0.4[H]/[Pd]

0.5

0.6

0.1
0.7

Fig. 4. Hydrogen concentration dependenceof output signal and equilibrium pressure forPd hydride. The dashed line for equilibriumpressure is guide to the eye.

our work
Hara et al.

60-93

magnetic susceptibility, χ' / 10 m /kg

xequilibrium pressure, P / kPa∆V10youtput voltage, ∆V , ∆V / µV

70100

1550403020
10000.10.2

0.3 0.4[H]/[Pd]

0.5

0.6

0.7

Fig. 5. Hydrogen concentration
dependence of magnetic susceptibility ofPd hydride. The figure includes the datareported by Hara et al.[5]ᄌൻߒߥ߆ߞߚ‫৻ޕ‬ᣇ‫∆ޔ‬Vy ߪ[H]/[Pd] = 0.2 ⒟ᐲ߹ߢ߶߷৻ቯߢ޽ࠅ‫ޔ‬0 ߢߪߥ޿᦭㒢ߩ୯ࠍ␜ߒߚ‫[ޕ‬H]/[Pd] > 0.2 ߢߪ‫∆ޔ‬Vy ߪ[H]/[Pd]ߩჇടߦᓥ޿න⺞ᷫዋߒ‫∆ޔ‬Vx ߇߶߷ 0 ߣߥࠆ[H]/[Pd] = 0.65 એ਄ߦ߅޿ߡ߽න⺞ᷫዋߒ 0 ߦߪߥࠄߥ߆ߞߚ‫ޕ‬೨ㅀߒߚࠃ߁ߦ‫੹ޔ‬࿁ታ㛎ߢ↪޿ߚ੤ᵹ⏛႐ߩᝄേᢙߪචಽዊߐ޿ߣ⠨߃ࠄࠇ‫ ߚ߹ޔ‬Pd ߪ Pauli Ᏹ⏛ᕈߢ޽ࠅᄢ߈ߥ⏛᳇ࡕ࡯ࡔࡦ࠻ࠍᜬߚߥ޿ߎߣ߆ࠄ‫∆ޔ‬Vy = 0 ࠍ␜ߔߪߕߢ޽ࠆ‫∆ߩߎޕ‬Vy ߇᦭㒢ߩ୯ࠍ␜ߔ
ේ࿃ߣߒߡ‫ޔ‬੤ᵹ⏛႐ਛߦ߅޿ߡ⹜ᢱਛߦ⊒↢ߔࠆ⺃ዉ㔚ᵹߦࠃࠆᓇ㗀߇⠨߃ࠄࠇࠆ‫ߟޕ‬߹ࠅ‫ޔ‬Pd ᳓⚛ൻ‛ߩ᳓⚛Ớᐲ߇Ⴧടߔࠆߎߣߢ Pd ☳ᧃ߇⤘ᒛߒ☳ᧃห჻ߩ⚿ว߇ᡷༀߐࠇࠆߚ߼‫⺃ޔ‬ዉ㔚ᵹߩࡄࠬ߇㐳ߊ᭴▽ߢ߈ࠆࠃ߁ߦߥࠅ‫⚿ޔ‬ᨐߣߒߡ⺃ዉ㔚ᵹߦࠃࠅ⊒↢ߔࠆ⏛᧤߇ᄢ߈ߊߥࠆߚ߼ߢߪߥ޿߆ߣផኤߢ߈ࠆ‫ޕ‬ૉߒ‫⸃ߩࠄࠇߎޔ‬ᨆߪᦝߥࠆ⹦⚦ߥ᷹ቯ෸߮⸃ᨆ߇ᔅⷐߣߥࠆߚ߼‫ᤨ⃻ޔ‬ὐߢߪߎࠇએ਄ߩᬌ⸛ߪⴕࠊߥ޿‫ޕ‬
࿑ 5 ߦ(17)ᑼࠍ↪޿ߡ∆Vx ߩ୯ࠍ⏛ൻ₸ χ ߦᄌ឵ߒߚ⚿ᨐࠍ␜ߔ‫ ߡߖࠊ޽ޕ‬SQUID ⏛᧤⸘ࠍ↪޿ߡ᷹ቯߐࠇߚㆊ෰ߩ᷹ቯ⚿ᨐ[7]ࠍ␜ߒߚ‫੹ޕ‬࿁᷹ቯߐࠇߚ⚿ᨐߣ‫ޔ‬ㆊ෰ߦ᷹ቯߐࠇߚ⚿ᨐߪ‫ޔ‬ቯ㊂⊛ߦࠃߊ৻⥌ߒߚ‫ޕ‬એ਄ࠃࠅ‫੹ޔ‬࿁᭴▽ߒߚ੤ᵹ⏛᧤⸘ߦࠃࠅ᳓⚛ൻ‛ߩ⏛ൻ₸߇᷹ቯน⢻ߢ޽ࠆߎߣ߇␜ߐࠇߚ‫ޕ‬
4. ߹ߣ߼
 ㊄ዻ᳓⚛ൻ‛᷹ቯ↪੤ᵹ⏛᧤⸘ࠍ૞⵾ߒ‫ߩߘޔ‬ᕈ⢻⹏ଔࠍⴕߞߚ‫ޕ‬૞⵾ߒߚ੤ᵹ⏛᧤⸘ߪ‫⹜ޔ‬ᢱࠍ᳓⚛㔓࿐᳇ࠃࠅขࠅ಴ߔߎߣήߊ᷹ቯ߇ߢ߈ࠆࠃ߁‫ޔ‬ᣢሽߩ PCT ᷹ቯⵝ⟎ࠍᡷㅧߖߕߦขࠅઃߌࠄࠇࠆࠃ߁⸳⸘ߒߚ‫ޕ‬Gd2O3 ☳ᧃࠍ↪޿ߡ⏛᧤⸘ߩᩞᱜࠍⴕߞߚߣߎࠈ‫ޔ‬᷹ቯ㔚࿶ߣ Gd2O3 ㊀㊂ߩ㑆ߢࠃ޿⋥✢㑐ଥ߇ᓧࠄࠇ‫ޔࠅࠃࠇߎޔ‬᷹ቯ㔚࿶߆ࠄ⏛ൻ₸߳ߩᄌ឵ᑼ෸߮⏛᧤⸘ߩಽ⸃⢻ 2.1710-9 m3/kg ߇ᓧࠄࠇߚ‫ ߡ޿↪ࠍ⟎ⵝᧄޕ‬Pd ᳓⚛ൻ‛ߩ⏛ൻ₸᷹ቯࠍⴕߞߚ⚿ᨐ‫ޔ‬ㆊ෰ߦႎ๔ߐࠇߚ୯ߣቯ㊂⊛ߦࠃߊ৻⥌ߒߚ‫ޕ‬એ਄ࠃࠅ‫ޔ‬੤ᵹ⏛᧤⸘ࠍ↪޿ߚ㊄ዻ᳓⚛ൻ‛ߩ⏛ൻ₸᷹ቯ߇චಽน⢻ߢ޽ࠆߎߣ߇␜ߐࠇߚ‫ޕ‬Reference[1]

K. Fukamichi, A. Fujita, and S Fujieda, Journal of Alloys and Compounds 408-412 (2006)
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M. van Gogh, W. H. Huisman, N. J. Koeman, B. Dam, J. H. Rector, S. Plota, M. Haaksma, R. M.
N. Hanzen, R. M. Jungblut, P. A. Duine, and R. Griessen, Natute 394 (1998) 656-658.

[3] ᣣᧄൻቇળ✬‫ޔ‬ᣂታ㛎⑼ቇ⻠ᐳ 3 ၮ␆ᛛⴚ 2 ⏛᳇㧔ਣༀ‫ޔ‬1976㧕p.97-109.
[4]

M. Nikolo, American Journal of Physics 63 (1995) 57-65.

[5]

L. Sagnotti, P. Rochette, M. Jackson, F. Vadeboin, J. Dinarès-Turell, A. Winkler, and“Mag-Net” Science Team, Physics of the Earth and Planetary Interiors 138 (2003) 25-38.

[6]

E. Wicke and H. Brodowsky: G. Alefeld and J. Völkl (Eds.), Hydrogen in Metals II.
Application-oriented Properties, (Springer-Verlag, Berlin, 1978).

[7]

M. Hara, J. Sakurai, S. Akamaru, K. Watanabe, K. Nishimura, K. Mori, M. Matsuyama,Materials Transactions 47 (2006) 2373-2376.