numerical renormalization group computation of magnetic relaxation rates

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We report an essentially exact numerical renormalization-group (NRG) computation of the temperature-dependent NMR rate $1/T_1$ of a probe at a distance $R$ from a magnetic impurity in a metallic host. We split the metallic states into two subsets, A and B. The former comprises electrons $a_k$ in $s$-wave states about the magnetic-impurity site. The coupling between the $a_k$ band and the impurity is described by the Anderson Hamiltonian, diagonalizable by the NRG procedure. Each state $b_k$ in the B subset is a linear combination of an $s$-wave state about the probe site with the degenerate $a_k$, constructed to be orthogonal to all the $a_k$'s. The $b_k$ band hence decouples from the impurity and is analytically treatable. We show that the relaxation rate has three components: (i) a constant associated with the $b_k$'s; (ii) a $T$-dependent term associated with the $a_k$'s, which decays in proportion to $1/(k_FR)^2$, where $k_F$ is the Fermi momentum; and (iii) another $T$-dependent term due to the interference between the $a_k$'s and the $b_k$'s. The interference term shows Friedel oscillations whose amplitude, proportional to $1/k_FR$, can be mapped onto the universal function of $T/T_K$ describing the Kondo resistivity. We compare our findings with results in the literature.

TRANSCRIPT

Numerical Renormalization-Group computationof magnetic relaxation rates

Krissia de Zawadzki, Luiz Nunes de Oliveira, Jose Wilson M. Pinto

Instituto de Fısica de Sao Carlos - Universidade de Sao Paulo

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 1 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Radius of Kondo screening cloud

Radius of Kondo screening cloud

𝑅𝑘

𝑅𝐾 ∝ 𝑇−1𝐾

General consensus

𝑅𝐾 = ~𝑣𝐹 /𝑘𝐵𝑇𝐾

Boyce &Slichter

NMR:

Experimental arrangement:

NMR probe: 𝑅 from the impurity

NRG computation of the spin

lattice relaxation rate 1/(𝑇1𝑇 ) as

function of 𝑇 and 𝑅

Can we measure 𝑅𝐾 via NMR?

Our findings:

Yes, we can!

T dependence changes as probe

crosses 𝑅𝐾

Phase of low-𝑇 Friedel oscillations

also changes

LASZLO, B. PRB, 75 (2007). BOYCE, J.B; SLICHTER, C.P. PRL, 32, 61 (1974).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Radius of Kondo screening cloud

Radius of Kondo screening cloud

𝑅𝑘

𝑅𝐾 ∝ 𝑇−1𝐾

General consensus

𝑅𝐾 = ~𝑣𝐹 /𝑘𝐵𝑇𝐾

Boyce &Slichter

NMR:

Experimental arrangement:

NMR probe: 𝑅 from the impurity

NRG computation of the spin

lattice relaxation rate 1/(𝑇1𝑇 ) as

function of 𝑇 and 𝑅

Can we measure 𝑅𝐾 via NMR?

Our findings:

Yes, we can!

T dependence changes as probe

crosses 𝑅𝐾

Phase of low-𝑇 Friedel oscillations

also changes

LASZLO, B. PRB, 75 (2007). BOYCE, J.B; SLICHTER, C.P. PRL, 32, 61 (1974).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Radius of Kondo screening cloud

Radius of Kondo screening cloud

𝑅𝑘

𝑅𝐾 ∝ 𝑇−1𝐾

General consensus

𝑅𝐾 = ~𝑣𝐹 /𝑘𝐵𝑇𝐾

Boyce &Slichter

NMR:

Experimental arrangement:

NMR probe: 𝑅 from the impurity

NRG computation of the spin

lattice relaxation rate 1/(𝑇1𝑇 ) as

function of 𝑇 and 𝑅

Can we measure 𝑅𝐾 via NMR?

Our findings:

Yes, we can!

T dependence changes as probe

crosses 𝑅𝐾

Phase of low-𝑇 Friedel oscillations

also changes

LASZLO, B. PRB, 75 (2007). BOYCE, J.B; SLICHTER, C.P. PRL, 32, 61 (1974).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Radius of Kondo screening cloud

Radius of Kondo screening cloud

𝑅𝑘

𝑅𝐾 ∝ 𝑇−1𝐾

General consensus

𝑅𝐾 = ~𝑣𝐹 /𝑘𝐵𝑇𝐾

Boyce &Slichter

NMR:

Experimental arrangement:

NMR probe: 𝑅 from the impurity

NRG computation of the spin

lattice relaxation rate 1/(𝑇1𝑇 ) as

function of 𝑇 and 𝑅

Can we measure 𝑅𝐾 via NMR?

Our findings:

Yes, we can!

T dependence changes as probe

crosses 𝑅𝐾

Phase of low-𝑇 Friedel oscillations

also changes

LASZLO, B. PRB, 75 (2007). BOYCE, J.B; SLICHTER, C.P. PRL, 32, 61 (1974).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Radius of Kondo screening cloud

Radius of Kondo screening cloud

𝑅𝑘

𝑅𝐾 ∝ 𝑇−1𝐾

General consensus

𝑅𝐾 = ~𝑣𝐹 /𝑘𝐵𝑇𝐾

Boyce &Slichter

NMR:

Experimental arrangement:

NMR probe: 𝑅 from the impurity

NRG computation of the spin

lattice relaxation rate 1/(𝑇1𝑇 ) as

function of 𝑇 and 𝑅

Can we measure 𝑅𝐾 via NMR?

Our findings:

Yes, we can!

T dependence changes as probe

crosses 𝑅𝐾

Phase of low-𝑇 Friedel oscillations

also changes

LASZLO, B. PRB, 75 (2007). BOYCE, J.B; SLICHTER, C.P. PRL, 32, 61 (1974).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

The quantum system

NRG Probe

Single-impurity Anderson model

𝐻 =

𝐻𝑐𝑜𝑛𝑑⏞ ⏟ ∑k

𝜀k𝑐†k𝑐k

+

𝐻𝑑⏞ ⏟ 𝜀𝑑𝑐

†𝑑𝑐𝑑 + 𝑈𝑛𝑑↑𝑛𝑑↓ +

𝐻𝑖𝑛𝑡⏞ ⏟ √Γ

𝜋(𝑓†

0𝑐𝑑 +𝐻.𝑐.)

𝜀 = 𝑣𝐹𝐷

(𝑘 − 𝑘𝐹 )

+𝐷

−𝐷

𝑘𝐹

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴[Ψ†

↑(��)Ψ↓(��)𝐼− +𝐻.𝑐.]

Ψ𝜇 =∑k

𝑒𝑖k.R𝑐k

1

𝑇1=

4𝜋

~

∑𝐼,𝐹

𝑒−𝛽𝐸𝐼 |⟨𝐼|𝐻𝑝𝑟𝑜𝑏𝑒|𝐹 ⟩|2𝛿(𝐸𝐼 − 𝐸𝐹 )

𝑓0 =1√𝜌

∑k

𝑐k

𝑅

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 3 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

The quantum system

NRG Probe

Single-impurity Anderson model

𝐻 =

𝐻𝑐𝑜𝑛𝑑⏞ ⏟ ∑k

𝜀k𝑐†k𝑐k +

𝐻𝑑⏞ ⏟ 𝜀𝑑𝑐

†𝑑𝑐𝑑 + 𝑈𝑛𝑑↑𝑛𝑑↓

+

𝐻𝑖𝑛𝑡⏞ ⏟ √Γ

𝜋(𝑓†

0𝑐𝑑 +𝐻.𝑐.)

𝜀 = 𝑣𝐹𝐷

(𝑘 − 𝑘𝐹 )

+𝐷

−𝐷

𝑘𝐹

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴[Ψ†

↑(��)Ψ↓(��)𝐼− +𝐻.𝑐.]

Ψ𝜇 =∑k

𝑒𝑖k.R𝑐k

1

𝑇1=

4𝜋

~

∑𝐼,𝐹

𝑒−𝛽𝐸𝐼 |⟨𝐼|𝐻𝑝𝑟𝑜𝑏𝑒|𝐹 ⟩|2𝛿(𝐸𝐼 − 𝐸𝐹 )

𝑓0 =1√𝜌

∑k

𝑐k

𝑅

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 3 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

The quantum system

NRG Probe

Single-impurity Anderson model

𝐻 =

𝐻𝑐𝑜𝑛𝑑⏞ ⏟ ∑k

𝜀k𝑐†k𝑐k +

𝐻𝑑⏞ ⏟ 𝜀𝑑𝑐

†𝑑𝑐𝑑 + 𝑈𝑛𝑑↑𝑛𝑑↓ +

𝐻𝑖𝑛𝑡⏞ ⏟ √Γ

𝜋(𝑓†

0𝑐𝑑 +𝐻.𝑐.)

𝜀 = 𝑣𝐹𝐷

(𝑘 − 𝑘𝐹 )

+𝐷

−𝐷

𝑘𝐹

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴[Ψ†

↑(��)Ψ↓(��)𝐼− +𝐻.𝑐.]

Ψ𝜇 =∑k

𝑒𝑖k.R𝑐k

1

𝑇1=

4𝜋

~

∑𝐼,𝐹

𝑒−𝛽𝐸𝐼 |⟨𝐼|𝐻𝑝𝑟𝑜𝑏𝑒|𝐹 ⟩|2𝛿(𝐸𝐼 − 𝐸𝐹 )

𝑓0 =1√𝜌

∑k

𝑐k

𝑅

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 3 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

The quantum system

NRG Probe

Single-impurity Anderson model

𝐻 =

𝐻𝑐𝑜𝑛𝑑⏞ ⏟ ∑k

𝜀k𝑐†k𝑐k +

𝐻𝑑⏞ ⏟ 𝜀𝑑𝑐

†𝑑𝑐𝑑 + 𝑈𝑛𝑑↑𝑛𝑑↓ +

𝐻𝑖𝑛𝑡⏞ ⏟ √Γ

𝜋(𝑓†

0𝑐𝑑 +𝐻.𝑐.)

𝜀 = 𝑣𝐹𝐷

(𝑘 − 𝑘𝐹 )

+𝐷

−𝐷

𝑘𝐹

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴[Ψ†

↑(��)Ψ↓(��)𝐼− +𝐻.𝑐.]

Ψ𝜇 =∑k

𝑒𝑖k.R𝑐k

1

𝑇1=

4𝜋

~

∑𝐼,𝐹

𝑒−𝛽𝐸𝐼 |⟨𝐼|𝐻𝑝𝑟𝑜𝑏𝑒|𝐹 ⟩|2𝛿(𝐸𝐼 − 𝐸𝐹 )

𝑓0 =1√𝜌

∑k

𝑐k

𝑅

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 3 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Two-center basis

Two-center basis

Spherically symmetric operators

𝑐𝜀 =∑k

𝑐 k 𝛿(𝜀− 𝜀k) (around impurity)

𝑑𝜀 =∑k

𝑐 k 𝑒𝑖k.R𝛿(𝜀− 𝜀k) (around probe)

𝑐 𝜀

𝑑 𝜀

NRG

analytical

{𝑐†𝜀, 𝑑𝜀′} = sin(𝑘𝑅)𝑘𝑅 𝛿(𝜀− 𝜀′)

Gram-Schmidt construction

𝑐𝜀𝜇 = 1√1−𝑊 2

(𝑑𝜀𝜇 −𝑊𝑐𝜀𝜇)

𝑊 = 𝑊 (𝜀,𝑅) = sin(𝑘𝑅)𝑘𝑅

𝑘𝑅 = 𝑘𝐹𝑅(1 + 𝜀

𝐷

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Two-center basis

Two-center basis

Spherically symmetric operators

𝑐𝜀 =∑k

𝑐 k 𝛿(𝜀− 𝜀k) (around impurity)

𝑑𝜀 =∑k

𝑐 k 𝑒𝑖k.R𝛿(𝜀− 𝜀k) (around probe)

𝑐 𝜀

𝑑 𝜀

NRG

analytical

{𝑐†𝜀, 𝑑𝜀′} = sin(𝑘𝑅)𝑘𝑅 𝛿(𝜀− 𝜀′)

Gram-Schmidt construction

𝑐𝜀𝜇 = 1√1−𝑊 2

(𝑑𝜀𝜇 −𝑊𝑐𝜀𝜇)

𝑊 = 𝑊 (𝜀,𝑅) = sin(𝑘𝑅)𝑘𝑅

𝑘𝑅 = 𝑘𝐹𝑅(1 + 𝜀

𝐷

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Two-center basis

Two-center basis

Spherically symmetric operators

𝑐𝜀 =∑k

𝑐 k 𝛿(𝜀− 𝜀k) (around impurity)

𝑑𝜀 =∑k

𝑐 k 𝑒𝑖k.R𝛿(𝜀− 𝜀k) (around probe)

𝑐 𝜀

𝑑 𝜀

NRG

analytical

{𝑐†𝜀, 𝑑𝜀′} = sin(𝑘𝑅)𝑘𝑅 𝛿(𝜀− 𝜀′)

Gram-Schmidt construction

𝑐𝜀𝜇 = 1√1−𝑊 2

(𝑑𝜀𝜇 −𝑊𝑐𝜀𝜇)

𝑊 = 𝑊 (𝜀,𝑅) = sin(𝑘𝑅)𝑘𝑅

𝑘𝑅 = 𝑘𝐹𝑅(1 + 𝜀

𝐷

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

NRG and Lanczos basis

NRG and Lanczos basis

𝐻𝑁 =1

𝒟𝑁

(𝑁−1∑𝑛=0

𝑡𝑛(𝑓†𝑛𝑓𝑛+1 +𝐻.𝑐.) +

√Γ

𝜋(𝑐†𝑑𝑓0 +𝐻.𝑐.) +𝐻𝑑

)NRG[4]

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴 [ 𝜙†↑𝜙↓ +Φ†

↑Φ↓ + (𝜙†↑Φ↓ +Φ†

↑𝜙↓) ] I− +𝐻.𝑐.

𝜙𝜇(𝑅) ≡∫ 𝐷

−𝐷

𝑑𝜀√

1 − 𝑊 (𝜀,𝑅)𝑐𝜀𝜇 Φ𝜇(𝑅) ≡∑𝑛

𝛾𝑛𝑓𝑛

analytically

numerically

1

𝑇1=

(1

𝑇1

)𝜙𝜙⏟ ⏞

1−𝑊 2𝐹

+

(1

𝑇1

)ΦΦ⏟ ⏞

𝑊 2𝐹

+

(1

𝑇1

)Φ𝜙⏟ ⏞

(1−𝑊𝐹 )𝑊𝐹

cte

𝑘𝐹𝑅≪

1

𝑘𝐹𝑅

≫1

DULL

SMALL

𝑊𝐹 =sin(𝑘𝐹𝑅)

𝑘𝐹𝑅

WILSON, K. Rev Mod Phys, 47, 773 (1975).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 5 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

NRG and Lanczos basis

NRG and Lanczos basis

𝐻𝑁 =1

𝒟𝑁

(𝑁−1∑𝑛=0

𝑡𝑛(𝑓†𝑛𝑓𝑛+1 +𝐻.𝑐.) +

√Γ

𝜋(𝑐†𝑑𝑓0 +𝐻.𝑐.) +𝐻𝑑

)NRG[4]

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴 [ 𝜙†↑𝜙↓ +Φ†

↑Φ↓ + (𝜙†↑Φ↓ +Φ†

↑𝜙↓) ] I− +𝐻.𝑐.

𝜙𝜇(𝑅) ≡∫ 𝐷

−𝐷

𝑑𝜀√

1 − 𝑊 (𝜀,𝑅)𝑐𝜀𝜇 Φ𝜇(𝑅) ≡∑𝑛

𝛾𝑛𝑓𝑛

analytically

numerically

1

𝑇1=

(1

𝑇1

)𝜙𝜙⏟ ⏞

1−𝑊 2𝐹

+

(1

𝑇1

)ΦΦ⏟ ⏞

𝑊 2𝐹

+

(1

𝑇1

)Φ𝜙⏟ ⏞

(1−𝑊𝐹 )𝑊𝐹

cte

𝑘𝐹𝑅≪

1

𝑘𝐹𝑅

≫1

DULL

SMALL

𝑊𝐹 =sin(𝑘𝐹𝑅)

𝑘𝐹𝑅

WILSON, K. Rev Mod Phys, 47, 773 (1975).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 5 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

NRG and Lanczos basis

NRG and Lanczos basis

𝐻𝑁 =1

𝒟𝑁

(𝑁−1∑𝑛=0

𝑡𝑛(𝑓†𝑛𝑓𝑛+1 +𝐻.𝑐.) +

√Γ

𝜋(𝑐†𝑑𝑓0 +𝐻.𝑐.) +𝐻𝑑

)NRG[4]

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴 [ 𝜙†↑𝜙↓ +Φ†

↑Φ↓ + (𝜙†↑Φ↓ +Φ†

↑𝜙↓) ] I− +𝐻.𝑐.

𝜙𝜇(𝑅) ≡∫ 𝐷

−𝐷

𝑑𝜀√

1 − 𝑊 (𝜀,𝑅)𝑐𝜀𝜇 Φ𝜇(𝑅) ≡∑𝑛

𝛾𝑛𝑓𝑛

analytically

numerically

1

𝑇1=

(1

𝑇1

)𝜙𝜙⏟ ⏞

1−𝑊 2𝐹

+

(1

𝑇1

)ΦΦ⏟ ⏞

𝑊 2𝐹

+

(1

𝑇1

)Φ𝜙⏟ ⏞

(1−𝑊𝐹 )𝑊𝐹

cte

𝑘𝐹𝑅≪

1

𝑘𝐹𝑅

≫1

DULL

SMALL

𝑊𝐹 =sin(𝑘𝐹𝑅)

𝑘𝐹𝑅

WILSON, K. Rev Mod Phys, 47, 773 (1975).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 5 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

NRG and Lanczos basis

NRG and Lanczos basis

𝐻𝑁 =1

𝒟𝑁

(𝑁−1∑𝑛=0

𝑡𝑛(𝑓†𝑛𝑓𝑛+1 +𝐻.𝑐.) +

√Γ

𝜋(𝑐†𝑑𝑓0 +𝐻.𝑐.) +𝐻𝑑

)NRG[4]

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴 [ 𝜙†↑𝜙↓ +Φ†

↑Φ↓ + (𝜙†↑Φ↓ +Φ†

↑𝜙↓) ] I− +𝐻.𝑐.

𝜙𝜇(𝑅) ≡∫ 𝐷

−𝐷

𝑑𝜀√

1 − 𝑊 (𝜀,𝑅)𝑐𝜀𝜇 Φ𝜇(𝑅) ≡∑𝑛

𝛾𝑛𝑓𝑛

analytically

numerically

1

𝑇1=

(1

𝑇1

)𝜙𝜙⏟ ⏞

1−𝑊 2𝐹

+

(1

𝑇1

)ΦΦ⏟ ⏞

𝑊 2𝐹

+

(1

𝑇1

)Φ𝜙⏟ ⏞

(1−𝑊𝐹 )𝑊𝐹

cte

𝑘𝐹𝑅≪

1

𝑘𝐹𝑅

≫1

DULL

SMALL

𝑊𝐹 =sin(𝑘𝐹𝑅)

𝑘𝐹𝑅

WILSON, K. Rev Mod Phys, 47, 773 (1975).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 5 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

NRG and Lanczos basis

NRG and Lanczos basis

𝐻𝑁 =1

𝒟𝑁

(𝑁−1∑𝑛=0

𝑡𝑛(𝑓†𝑛𝑓𝑛+1 +𝐻.𝑐.) +

√Γ

𝜋(𝑐†𝑑𝑓0 +𝐻.𝑐.) +𝐻𝑑

)NRG[4]

𝐻𝑝𝑟𝑜𝑏𝑒 = −𝐴 [ 𝜙†↑𝜙↓ +Φ†

↑Φ↓ + (𝜙†↑Φ↓ +Φ†

↑𝜙↓) ] I− +𝐻.𝑐.

𝜙𝜇(𝑅) ≡∫ 𝐷

−𝐷

𝑑𝜀√

1 − 𝑊 (𝜀,𝑅)𝑐𝜀𝜇 Φ𝜇(𝑅) ≡∑𝑛

𝛾𝑛𝑓𝑛

analytically

numerically

1

𝑇1=

(1

𝑇1

)𝜙𝜙⏟ ⏞

1−𝑊 2𝐹

+

(1

𝑇1

)ΦΦ⏟ ⏞

𝑊 2𝐹

+

(1

𝑇1

)Φ𝜙⏟ ⏞

(1−𝑊𝐹 )𝑊𝐹

cte

𝑘𝐹𝑅≪

1

𝑘𝐹𝑅

≫1

DULL

SMALL

𝑊𝐹 =sin(𝑘𝐹𝑅)

𝑘𝐹𝑅

WILSON, K. Rev Mod Phys, 47, 773 (1975).

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 5 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Friedel oscillations

Friedel oscillations

9.8 10.0 10.2 10.4 10.6 10.8 11.0 11.2kFRπ

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

10.5π

10π 10.25π

T=1.7569e−4

T=9.8711e−8

10.0 10.5 11.0

0.16

0.17

1T

1T(kFR

)2

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 6 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Relaxation rate - temperature dependence

𝑘𝐵𝑇𝐾 = 1.25× 10−5

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

(101+0.25)π

(102+0.25)π

(103+0.25)π

(104+0.25)π

(105+0.25)π

(106+0.25)π

(107+0.25)π

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 7 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Interference relaxation rate

Interference relaxation rate

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-20

1

2

3

4

5

6

7

R≈RK

outside

inside

(kFR

)2

kBT

( 1 T1

)

kB T

kFR=(n+14)π

λB =2πvFkB T

de Broglie

n=102

n=105

n=107

n=102

n=105

n=107

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 8 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Friedel oscillations

Friedel oscillations

101 102 103 104 105 106 107 108

kFRπ

1.58

1.60

1.62

1.64

1.66

1.68

1.70

1.72

RK →TK =1.25e−05

(n+1/2)π

104 105 106

0.00010

0.00015

+1.6131

1T

1T(kFR

)2

T≈5.62e−11

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 9 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Conclusions

NMR to measure 𝑅𝐾 : OK!

Inside cloud, 𝑇 -dependent rate follows universal curve

Outside cloud, rate follows different curve

Phase of Friedel oscillations reverses around 𝑅 = 𝑅𝐾

Future prospects:

Other geometries

P-h symmetric case differs from assymetric ?

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 10 / 11

Introduction NRG calculations Numerical results Conclusions Acknowledgment

Acknowledgment

Thank you!

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 11 / 11

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 1 / 4

Additional results

Relaxation rate - 𝒢𝑠𝑖𝑑𝑒(𝑇 ) profile

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

(101+0.5)π

(102+0.5)π

(103+0.5)π

(104+0.5)π

(105+0.5)π

(106+0.5)π

(107+0.5)π

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 2 / 4

Additional results

Relaxation rate - 𝒢𝑆𝐸𝑇 (𝑇 ) profile

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

101 π

102 π

103 π

104 π

105 π

106 π

107 π

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 3 / 4

Additional results

Particle-hole symmetric case

Particle-hole symmetric case: 1/𝑇1 as function of 𝑇

𝑘𝐹𝑅 = 𝑛𝜋 and 𝑘𝐹𝑅 = (𝑛+ 12 )𝜋, 𝑛 = 10

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

10-9 10-8 10-71.4

1.6

1.8

2.0

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 4

Additional results

Particle-hole symmetric case

Particle-hole symmetric case: 1/𝑇1 as function of 𝑇

𝑘𝐹𝑅 = 𝑛𝜋 and 𝑘𝐹𝑅 = (𝑛+ 12 )𝜋, 𝑛 = 103

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

10-8 10-71.4

1.6

1.8

2.0

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 4

Additional results

Particle-hole symmetric case

Particle-hole symmetric case: 1/𝑇1 as function of 𝑇

𝑘𝐹𝑅 = 𝑛𝜋 and 𝑘𝐹𝑅 = (𝑛+ 12 )𝜋, 𝑛 = 105

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

10-7

1.6

1.8

2.0

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 4

Additional results

Particle-hole symmetric case

Particle-hole symmetric case: 1/𝑇1 as function of 𝑇

𝑘𝐹𝑅 = 𝑛𝜋 and 𝑘𝐹𝑅 = (𝑛+ 12 )𝜋, 𝑛 = 107

10-10 10-9 10-8 10-7 10-6 10-5 10-4 10-3 10-2 10-1

kB T

0

1

2

3

4

5

6

7

10-91

2

3

4

(kFR

)2

kBT

( 1 T1

)

Zawadzki, K. de; Oliveira, L.N.; Pinto, J.W.M. NRG computation of nuclear magnetic relaxation rates 4 / 4

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